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Associations of sociodemographic, psychosocial, and behavioral factors with sexual risk and sexually transmitted diseases in teen clinic patients.

PURPOSE: To examine the influence of sociodemographic characteristics, sexually transmitted disease (STD)/human immunodeficiency virus knowledge, and psychosocial and behavioral risk factors on sexual risk and STDs in adolescents using constructs from the Information, Motivation, and Behavioral Skills model (IMB). METHODS: A convenience sample of 303 sexually experienced, racially diverse adolescents (mean age 16.7 years, 57.9% female) who were seeking health care at a general health maintenance organization teen clinic were recruited for the study and completed a self-reported questionnaire which assessed sociodemographic, knowledge, and psychosocial factors, risk behaviors, and history of STDs. Multiple regression analyses were used to assess factors associated with sexual risk behavior and STD history. RESULTS: Many of the study participants were at risk for STDs; 43.8% had four or more lifetime sexual partners, 62.8% did not consistently use condoms, 21.1% had a history of pregnancy or impregnation, and 28.2% had a history of STDs. A multiple linear regression model to assess factors associated with sexual risk behavior (a nine-item index) indicate that perceptions of higher STD risk, perceptions that friends engage in risk behaviors, perceptions that friends will not support their STD risk-reduction efforts, knowing someone of a similar age who has had an STD, and having no intention of using condoms in the future are significantly associated with sexual behavioral risk (R(2) =.22, p <.000). A logistic regression model to examine history of STDs reveals that teens who are female, African-American, frequently use marijuana, have an older steady sexual partner, have a history of pregnancy or impregnation, have a greater number of lifetime sexual partners, and perceive that monogamy will not decrease STD risk are significantly more likely to report a history of STDs. CONCLUSIONS: Sociodemographic factors and constructs of the IMB model are associated with adolescents' risk and acquisition of STDs. Teens with such risk profiles should be targeted for risk-reduction intervention.

Adolescent↗

Nitrogen dioxide prediction in Southern California using land use regression modeling: potential for environmental health analyses.

We modeled the intraurban distribution of nitrogen dioxide (NO(2)), a marker for traffic pollution, with land use regression, a promising new exposure classification technique. We deployed diffusion tubes to measure NO(2) levels at 39 locations in the fall of 2003 in San Diego County, CA, USA. At each sample location, we constructed circular buffers in a geographic information system and captured information on roads, traffic flow, land use, population and housing. Using multiple linear regression, we were able to predict 79% of the variation in NO(2) levels with four variables: traffic density within 40-300 m of the sampling location, traffic density within 300-1000 m, length of road within 40 m and distance to the Pacific coast. Applying this model to validation samples showed that the model predicted NO(2) levels within, on average, 2.1 p.p.b for 12 training sites initially excluded from the model. Our evaluation of this land use regression model showed that this method had excellent prediction and robustness in a North American context. These models may be useful tools in evaluating health effects of long-term exposure to traffic-related pollution.

California↗

Early postoperative complications of splenectomy for hematologic disease.

Splenectomy may be indicated in a variety of hematologic diseases for diagnostic reasons, therapeutic reasons, or both. Most reviews reveal a high proportion of procedures performed as part of the staging process for Hodgkin disease. Splenectomy for myelofibrosis has been associated with an increased postoperative complication rate. Other determinants of morbidity have been splenic weight and operative blood loss. The authors reviewed a series of 83 adult patients from a prospective database established in 1991 to determine the incidence of early postoperative complications associated with splenectomy for hematologic disease and to analyze patient characteristics that may predict their occurrence. Morbidity that occurred within 30 days of splenectomy was considered to be an early postoperative complication. Operative estimated blood loss and incidence of postoperative complications were correlated with patient age, preoperative platelet count, splenic weight, and diagnosis of myelofibrosis as regression covariates. Indications for splenectomy were therapeutic in 76 patients (92%). Median splenic weight was 760 g, and 22 patients had massive splenomegaly. Patients with splenic weight more than 1,500 g had a significantly higher median estimated blood loss (300 ml; p = 0.02). Splenic weight was the main determinant of estimated blood loss in a multiple linear regression analysis (p = 0.02). Twenty-two patients (27%) experienced postoperative complications and five of those patients died (6%). Patients with myelofibrosis had the highest incidence of complications (50%) and the highest postoperative mortality (21%; p = 0.04). In a logistic regression model, estimated blood loss was the only variable significantly correlated with postoperative complications (p = 0.02). Splenectomy for hematologic disease is associated with an acceptable early postoperative complication rate, even when the indication is predominantly therapeutic. Patients at particularly high risk include those with elevated operative blood loss, massive splenomegaly, and myelofibrosis.

Adult↗

Caries and fluorosis prevalence in communities with different concentrations of fluoride in the water.

The need to defluoridate and fluoridate the water supplies in areas with drinking water naturally containing above-optimal (>/=2.5 mg/l) and suboptimal (</=0.3 mg/l) fluoride concentration and caries and fluorosis prevalence of 12-year-old schoolchildren were assessed in Italy. In the low-fluoride area, 48.4% children were caries-free (DMFT = 0) and the DMFT and DMFS were 1.5 and 2.6; in the high-fluoride area, 46.8% had a DMFT = 0 and the values of the indices were 1.4 and 1.6, respectively. Multiple logistic regression analysis showed a significant association in the caries-free status according to parents' employment status (OR = 1.2, 95% CI = 1.1-1.3) and children's sweets consumption, since children who consumed sweets at least once a day had an adjusted odds ratio of 1.8 (95% CI = 1.4-2.3) compared to those with a lower consumption. Multiple linear regression analysis showed that DMFT and DMFS were significantly higher in children with a lower socioeconomic status and in those who consumed sweets at least once a day, with the DMFS significantly associated also with the area of residence. DT and FT scores were higher in the high- and low-fluoride areas, respectively. No evidence of fluorosis was reported in 94.5 and 55.3% of children in the low- and high-fluoride areas, respectively. The Community Fluorosis Index (CFI) for all permanent teeth was significantly higher in the high-fluoride area, 0.8, than the value, 0.1, found in the low-fluoride community. Our results substantiate the difficulties in defining universal guidelines for the fluoridation or defluoridation of drinking water and the need for an epidemiological approach to the decision as to fluoridate and defluoridate the water supply.

Analysis of Variance↗

Factors delaying hospital admission after stroke in Leicestershire.

BACKGROUND AND PURPOSE: Use of thrombolysis and acute treatments for cerebral infarction may require that acute stroke be treated as a medical emergency. To assess the factors influencing the time to admission in acute stroke, we conducted a prospective study of all such patients admitted to the hospitals in Leicester, UK, over a 12-month period. METHODS: Factors assessed were age, sex, time of stroke onset, stroke severity, home circumstances, and routes of admission. Initial between-group comparisons were made with the Mann-Whitney U test. The individual contribution of each of these variables was assessed with multiple linear regression analysis. RESULTS: An accurate time of stroke onset was identified in 374 (70%) of 535 registered patients (median age 77 [range, 29-98] years; 332 men, 203 women). Median time from onset to admission was 6 hours, with 25% of the patients arriving in less than 2.5 hours and 75% in less than 11.5 hours. Multiple regression confirmed that only admission through the bed allocation bureau (p less than 0.001), living alone (p less than 0.001), and nocturnal onset (p = 0.003) prolonged delay time. Despite patients over 70 years of age taking a median of 7 hours from onset to admission compared with 4 hours for those under age 70 (p less than 0.001), the effect of age appeared to be dependent on these three factors. Age, sex, level of consciousness, rural domicile, and place of admission did not influence the delay time independently. CONCLUSIONS: We have identified some of the factors affecting the hospital admission delay time for stroke. With the possible advent of effective early treatments for stroke, these factors will need to be addressed.

Adult↗

The single-breath N2-test and spirometry in healthy non-smoking males.

Healthy males (aged 30-70), who had never smoked, were studied. The 178 subjects were selected by systematic sampling from an urban population. Using the single-breath N2-washout test we measured the closing volume (CV) and the slope of the alveolar plateau (delta N2). A prediction equation for CV was produced by simple regression on age. delta N2 showed an accelerated increase with age above the age of 50. A curvilinear equation was established: delta N2 (%/1) = 0.85 + e0.0929 x A( yrs ) -6.302. Reference equations were also established for vital capacity (VC), forced expiratory volume in one second (FEV1) and FEV1 in per cent VC (FEV%) by means of linear multiple regression on age and height. The distribution of delta N2 was not homogenous throughout the age-range. As an upper limit of the reference range, we suggest 180% of the predicted value.

Adult↗

Genotypes of the cytochrome p450 isoform, CYP2C9, and the vitamin K epoxide reductase complex subunit 1 conjointly determine stable warfarin dose: a prospective study.

BACKGROUND: Warfarin has a narrow therapeutic range and wide inter-individual dosing requirements that may be related to functional variants of genes affecting warfarin metabolism (i.e., CYP2C9) and activity (i.e., vitamin K epoxide reductase complex subunit 1-VKORC1). We hypothesized that variants in these two genes explain a substantial proportion of variability in stable warfarin dose and could be used as a basis for improved dosing algorithms. METHODS: Consecutive consenting outpatients (n = 213) with stable INR (2-3) for >1 month were enrolled. Buccal DNA was extracted using a Qiagen mini-column and CYP2C9*2 and VKORC1 genotyping performed by the Taqman 3' nuclease assay. Sequencing for CYP2C9*3, genotyping was done using Big Dye v3.1 terminator chemistry Dose by genotype was assessed by linear regression. RESULTS: Weekly warfarin dose averaged 30.8 +/- 13.9 mg/week; average INR was 2.42 +/- 0.72. CYP2C9*2/*3 genotype distribution was: CC/AA (wild-type [WT]) = 71.4%, CT/AA = 18.3%, CC/AC = 9.4%, and CT/AC = 1%; VKORC1 genotypes were CC (WT) = 36.6%, CT = 50.7%, and TT = 12.7%. Warfarin doses (mg/week) varied by genotype: for CYP2C9, 33.3 mg/week for WT (CC/AA), 27.2 mg/week for CT/AA (P = 0.04 vs. WT), 23.0 mg/week for CC/AC (P = 0.003), and 6.0 mg/week for CT/AC (P < 0.001), representing dose reductions of 18-31% for single and 82% for double variant carriers; for VKORC1: 38.4 mg/week for WT (CC), 28.6 mg/week for CT (P < 0.001 vs. WT), 20.95 mg/week for TT (P < 0.001). In multiple linear regression, genotype was the dominant predictor of warfarin dose (P = 2.4 x 10(-15)); weak predictors were age, weight, and sex. Genotype-based modeling explained 33% of dose-variance, compared with 12% for clinical variables alone. CONCLUSION: In this large prospective study of warfarin genetic dose-determinants, carriage of a single or double CYP2C9 variant, reduced warfarin dose 18-72%, and of a VKORC1 variant by 65%. Genotype-based modeling explained almost one-half of dose-variance. A quantitative dosing algorithm incorporating genotypes for 2C9 and VKORC1 could substantially improve initial warfarin dose-selection and reduce related complications.

Adult↗

Skin tissue cholesterol assay correlates with presence of coronary calcium.

BACKGROUND: Keratinocytes maintain cholesterol homoeostasis using LDL and HDL-scavenger receptor pathways implicated in atherosclerosis. We tested whether skin tissue cholesterol (SkTC) is associated with subclinical atherosclerosis, assessed using carotid intima-medial thickness (IMT) and coronary artery calcification (CAC). METHODS: Two hundred and twenty two subjects were recruited from the Baltimore site of the Multi-Ethnic Study of Atherosclerosis (MESA). Baseline MESA examination included fasting blood collection, IMT measurement by B-mode ultrasound and CAC determination by helical CT. SkTC was measured using the Cholesterol 1, 2, 3 kit (IMI Inc., Canada). RESULTS: SkTC was significantly higher if CAC was present in Caucasians (p = 0.04) but not African-Americans. SkTC was not significantly correlated with IMT in either group. Using multiple logistic regression adjusting for age, sex and serum lipids, a 1-standard deviation higher SkTC was associated with 187% higher odds of the presence of CAC in Caucasians (p < 0.01) but no significant difference in odds for African-Americans. In subjects in whom CAC was present, the extent of CAC was not related to the SkTC in multiple linear regressions. CONCLUSIONS: SkTC was associated with the presence of CAC independently of serum lipids/lipoproteins in Caucasians but not African-Americans. SkTC may provide a useful indicator of subclinical atherosclerosis in Caucasians.

Black or African American↗

Apnea is associated with neurodevelopmental impairment in very low birth weight infants.

OBJECTIVE: To determine whether apnea in preterm infants is associated with abnormal neurodevelopmental outcome. METHODS: We determined the number of days that apnea and bradycardia spells were noted by the nursing staff, during the initial hospitalization of 175 preterm infants of less than <1250 g birth weight or <32 weeks gestation who had been enrolled in the follow-up program of the Royal Victoria Hospital. Multiple logistic and multiple linear regression models were constructed to determine the relationships between apnea days and neurodevelopmental impairment at 3 years of age, after correcting for gestation, sex, intrauterine growth restriction, intraventricular hemorrhage, periventricular leukomalacia, pre- and postnatal steroids, and maternal education. RESULTS: A total of 41 infants had neurodevelopmental impairment (Bayley MDI or PDI <70, cerebral palsy or blindness). By multiple logistic regression, an increasing number of days on which at least one apnea occurred, "total apnea days", and male sex were significantly associated with increasing probability of neurodevelopmental impairment, p<0.01, the sum of days of assisted ventilation and apnea days occurring after extubation was also associated with impairment in a separate regression model, p<0.001. Lower MDI at 3 years was significantly associated with postnatal steroid use, p=0.004. Lower PDI was associated with increasing apnea days, male sex, and postnatal steroid use, p<0.001. Functional impairment (a score on any one of the four dimensions of the Vineland scale <70), found in 17% of the infants, was associated with increasing apnea days, p<0.05. Caffeine treatment was not independently associated with any outcome. CONCLUSION: An increasing number of days that apnea was recorded during hospitalization was associated with a worse outcome. Among the potential explanations for this finding is the possibility that multiple recurrent hypoxic and bradycardic spells may cause brain injury.

Apnea↗

Increased resting energy expenditure in hemodialysis patients with severe hyperparathyroidism.

Several metabolic derangements, including enhanced protein catabolism, have been suggested to be associated with increased circulating parathyroid hormone (PTH) in patients with secondary hyperparathyroidism (HPT). Such conditions, therefore, might lead to an increase in energy expenditure. The present study examined by indirect calorimetry the resting energy expenditure (REE) of 15 hemodialysis patients who have severe HPT (PTH = 1457 +/- 676 pg/ml) and were pair-matched for age and gender to 15 hemodialysis patients with mild to moderate HPT (PTH = 247 +/- 196 pg/ml). Both groups were also pair-matched for age and gender to a group of 15 healthy adult subjects (control). In six patients from the severe HPT group submitted to total parathyroidectomy, REE was determined 6 mo after the surgery. The groups were not different regarding lean body mass (LBM) measured by bioelectric impedance, serum C-reactive protein, and bicarbonate. Thyroid-stimulating hormone was within the normal range in all groups. Nonadjusted REE was significantly higher in the severe HPT group (1674 +/- 337 kcal/d) compared with patients with mild to moderate HPT (1388 +/- 229 kcal/d; P < 0.05). Both groups did not differ from the control group (1468 +/- 323 kcal/d). When adjustment of REE for LBM was performed using the multiple regression analysis, patients with mild to moderate HPT and control subjects had significantly lower REE (-231 and -262 kcal, respectively) than that of the severe HPT group. Considering all patients together, nonadjusted REE correlated directly with LBM (r = 0.61; P < 0.01). PTH correlated strongly with LBM in the severe HPT group (r = -0.82; P < 0.01). In the multiple linear regression analysis, only LBM and PTH were independent determinants of REE (n = 30; R(2) = 0.47). REE decreased significantly in the six patients who were evaluated 6 mo after parathyroidectomy (from 1617 +/- 339 to 1226 +/- 253; P = 0.02). These results demonstrate that hemodialysis patients with severe HPT have increased REE that might be reduced after parathyroidectomy.

Adult↗

The -1131 T>C and S19W APOA5 gene polymorphisms are associated with high levels of triglycerides and apolipoprotein C-III, but not with coronary artery disease: an angiographic study.

High plasma concentrations of triglycerides (TG) and apolipoprotein C-III (ApoC-III) are well-known risk factors for cardiovascular disease. Two variants of the recently discovered APOA5, 1131 C>T and S19W, have been associated with hypertriglyceridemia, whereas their relation with coronary artery disease (CAD) remains controversial. Nine hundred and thirteen angiografically defined patients (669 CAD and 244 CAD-free) were genotyped for APOA5 -1131 C>T and S19W polymorphisms. Carriership of the APOA5 -1131 C allele was identified, by multiple linear regression models, as a significant independent predictor for both TG (standardized beta-coefficient=0.112; p=0.010) and ApoC-III variability (standardized beta-coefficient=0.113; p=0.013). Similarly, APOA5 19W allele carriership was a significant independent predictor for both TG (standardized beta-coefficient=0.113; p=0.007) and ApoC-III variability (standardized beta-coefficient=0.088; p=0.045). Despite the association with at-risk lipid profile, no significant difference was detected in the distribution of both APOA5 gene polymorphisms between subjects with or without CAD. Moreover, homozygous carriers of the APOC3 -455 C, another TG- and ApoC-III raising variant, showed a significant increased risk for CAD (OR 1.90 with 95% CI 1.002-3.62; p=0.049; by multiple logistic regression). Different genotypes, i.e., APOA5 and APOC3 variants, may lead to similar biochemical phenotypes, namely hypertriglyceridemia, but to contrasting clinical phenotypes such as the presence of angiographically proven CAD.

Adult↗

Research on adverse drug events. I. Muscarinic M3 receptor binding affinity could predict the risk of antipsychotics to induce type 2 diabetes.

Antipsychotics are associated with a wide range of adverse effects, several of which may represent a serious health risk to patients. There is an increased concern about metabolic disturbances associated with antipsychotics, including weight gain, dyslipidemia, hyperglycemia, and type 2 diabetes. However, little is known about the mechanisms underlying antipsychotic-induced metabolic disturbances and, in particular, those related to the induction of abnormal glucose metabolism and diabetes. The present article aimed to identify those receptor(s) that are most likely to be involved with or mediate antipsychotics-induced diabetes. Two independent measures taken from literature to indicate the risk of type 2 diabetes associated with 25 typical and atypical antipsychotic drugs were considered, along with their binding affinities to 21 specific receptors (obtained from the resources of Prous Science Integrity). A range of both exploratory and predictive statistical analyses were applied, including principal component factorial analysis, multivariable linear regression analysis, and discriminant analysis. Binding affinities (pKi) to human neurotransmitter receptors and monoaminergic transporters were used as independent variables (predictors). Measures to determine the risk to induce new-onset type 2 diabetes associated with each antipsychotic, logistic regression odds-ratio (dOR) and a discrete scale-based risk (three levels: 'low,' 'moderate,' 'high'), were used as the dependent variables (criteria). Similarly, parallel analyses were also conducted for other measures (average effective therapeutic dose) or adverse effects (weight gain, extrapyramidal side effects, hyperprolactinemia, anticholinergic, hypotension, and sedation) associated with antipsychotics, where underlying mechanisms have been previously established and, therefore, serve as positive-control references. Affinity for the cholinergic muscarinic M3 receptor subtype was presented as the best predictor for the propensity of antipsychotics to induce type 2 diabetes. This was independently revealed by means of multiple linear regression analysis, using the dOR as criterion (R=0.90, p<0.0001), and discriminant analysis, using the scale-based risk of type 2 diabetes (3 levels) as criterion (Wilks' lambda=0.33, chi2=14.11, p<0.001). To our knowledge, this study provides the first direct evidence to indicate that antipsychotic agents with high binding affinity to the muscarinic M3 receptor are associated with an elevated risk for type 2 diabetes. Rationale of the M3 receptor involvement in this adverse effect is discussed further in relation to M3 receptor mediation of glucose-dependent parasympathetic acetylcholine regulation of insulin secretion by pancreatic beta-cells. This study is the first in a series of investigations that aim to further our understanding of mechanisms underlying adverse drug effects.

Antipsychotic Agents↗

Predictions of protein secondary structures using factor analysis on Fourier transform infrared spectra: effect of Fourier self-deconvolution of the amide I and amide II bands.

Fourier self-deconvolution (FSD) was performed on protein amide I and II Fourier transform infrared (FTIR) spectra to test if the resultant increased band shape variation would lead to improvements in protein secondary structure prediction with our factor analysis based restricted multiple regression (RMR) methods. FTIR spectra of 23 proteins dissolved in H2O were measured and normalized to a constant amide I peak absorbance. The deconvolved spectra were renormalized by area so that the deconvolved spectra sets had the same area as before. Principal component analysis of the deconvolved spectra sets was carried out, which was followed by a selective multiple linear regression (RMR) analysis of the principal component loadings with regard to the fractional components (FC) of secondary structure. As compared to analyses based on the original spectra set, helix and sheet predictions were not noticeably improved by FSD; but, if a very large number of component spectra (16) were retained in the pool to select which loadings to be used in the RMR optimization, better predictions of turn and "other" resulted. The prediction quality varied depending on the deconvolution parameters used.

Animals↗

Relationships of physical activity with dietary behaviors among adults.

BACKGROUND: Physical activity and diet are important influences on health, but few data are available about the relationship between these two factors. The purpose of this study was to examine relationships between physical activity and dietary quality and to identify determinants of the combination of sedentary behavior and suboptimal diet. METHODS: The design of this study was cross-sectional. The setting was a large managed-care organization and the participants were 1,322 racially diverse men and women ages 25-91 years. We categorized subjects' physical activity into vigorous, moderate, and sedentary based on answers to two validated interviewer-administered questions about intensity and duration of specified activities. Dietary assessment was by means of a validated short food frequency questionnaire. We defined suboptimal diet as consuming unhealthful quantities of at least two of the following five food groups: fruits, vegetables, whole grain foods, whole-fat dairy foods, and red and processed meats. RESULTS: Seven hundred fifty-four (57%) subjects were sedentary and 617 (47%) consumed a suboptimal diet. Using multiple linear regression, we found that sedentary individuals consumed smaller amounts of foods and nutrients considered to be healthful, such as fruits and vegetables, fiber, calcium, folate, and vitamins A, C, and E, than more active participants. For nutrients considered to be harmful, such as saturated fat, trans fat, and dietary cholesterol, the association with physical activity was inverse. In multiple logistic regression analyses, the strongest sociodemographic correlates of the joint presence of inactivity and poor diet were less education [odds ratio for 1-year decrease 1.14 (95% confidence interval 1.06, 1.22)], nonwhite race [1.48 (1.05, 2.07)], and nonmarried status [1.49 (1.06, 2.10)]. CONCLUSIONS: Physical activity and diet quality are correlated behaviors. Suboptimal diet and sedentary behavior tend to cluster in individuals who are less educated, not married, and of nonwhite race. Programs that target diet and activity together, informed by their joint determinants, may attain enhanced outcomes.

Adult↗

Symptomatic hypothalamic-pituitary dysfunction in nasopharyngeal carcinoma patients following radiation therapy: a retrospective study.

Endocrine assessment was performed in 32 relapse-free southern Chinese patients (21 males and 11 females, aged 27-50 years at the time of assessment) 5-17 years following radiation therapy (RT) alone for early nasopharyngeal carcinoma (NPC). Initial screening was done using questionnaires emphasizing on impaired sexual function and menstrual disturbance plus measurement of serum levels of thyroxine, free thyroxine index, thyrotropic hormone, prolactin, and additionally testosterone for males only. Those showing abnormalities were subjected to detailed pituitary function tests. Hypothalamic-pituitary dysfunction was found in 7 female patients and only 1 male patient. A delayed TSH response to thyrotropin releasing hormone suggesting a hypothalamic disorder was seen in 6 of the affected female patients, and hyperprolactinaemia in also 6. None of the patients had evidence of diabetes insipidus. Hypopituitarism became symptomatic 2-5 years after RT with a mean latent interval of 3.8 years. A practical protocol for regular endocrine assessment for NPC patients after RT has been proposed. Multiple linear regression analysis of the radiotherapeutic data from the 11 female patients indicates that the likelihood of late occurrence of symptomatic hypothalamic-pituitary dysfunction following RT is dependent on the TDF of the target dose to the nasopharyngeal region and the height of the upper margin of the opposed lateral facial fields above the diaphragma sellae (coefficient of multiple correlation = 0.9025). Except when the sphenoid sinus or the middle cranial fossa is involved, it is advisable to set the height of the upper margin of the lateral facial field at a level no higher than the diaphragma sellae. The hypothalamus and possibly the pituitary stalk as well may sustain permanent damage by doses of radiation within the conventional radiotherapeutic range for carcinomas.

Adult↗

Tobacco use and readiness to quit smoking in low-income HIV-infected persons.

The study aim was to identify covariates of smoking status and readiness to quit that encompassed key sociodemographic and health status variables, health-related quality of life, drug use and unprotected sex, and tobacco use variables in a cohort of low-income persons living with HIV. We also examined the impact of HIV diagnosis on smoking cessation. The sample (N = 428) was mostly male (59%) and Black (53%) or Hispanic (30%), and had a high school education or less (87%). Mean age was 40 years. Two-thirds of participants were current smokers, 19% former smokers, and 16% never smokers. Current smokers smoked a mean of 16 cigarettes/day for 22 years; 42% were in the precontemplation stage of readiness to quit smoking, 40% were contemplators, and 18% were in preparation. Most current smokers (81%) reported receiving medical advice to quit smoking. Multivariate logistic regression analyses indicated that current smokers, compared with former smokers, were more likely to use illicit drugs, perceive a lower health risk for continued smoking, and report less pain. Current smokers, compared with nonsmokers (former and never smokers), were more likely to report greater illicit drug use in their lifetime, current illicit drug use, and less pain. A multiple linear regression indicated that greater current illicit drug use, greater emotional distress, and a lower number of quit attempts were associated with lower stage of readiness to quit smoking. These findings confirm a high prevalence of smoking among HIV-infected persons and suggest a complex interplay among drug use, pain, and emotional distress that impact smoking status and, among smokers, readiness to quit. Tobacco control programs for HIV-infected persons should build motivation to quit smoking and address salient barriers to cessation--such as comorbid drug use, emotional distress, pain, and access to and coverage for treatment--and should educate smokers regarding the HIV-specific health benefits of cessation.

Adult↗

The relationship of the baseline ECG to blood pressure change.

A total of 1,090 male participants (aged 23 to 80 years) of the Normative Aging Study who had baseline BP less than 140/90 mm Hg were observed prospectively for ten years. Blood pressures were taken at five- and ten-year follow-up examinations. Multiple linear regression analysis indicated that baseline levels of systolic pressure, age, R-wave amplitude (aVL), hematocrit, T-wave amplitude (V5), and S-wave amplitude (V4, V5, and V6) were statistically significant predictors of systolic pressure change. Baseline levels of diastolic pressure, R-wave amplitude (aVL), and hematocrit were statistically significant predictors of diastolic pressure change. Multiple logistic regression analysis showed that baseline levels of BP, S-wave amplitude (V1, V2, and V3), body mass index, R-wave amplitude (V4, V5, and V6), and T-wave amplitude (V5) were statistically significant predictors of subsequent hypertension. Whether the identified ECG amplitudes are an indicator of early increases in peripheral resistance or a function of neurohumoral factors, or both, is unknown.

Adult↗

Prognosis versus actual outcome. II. The effectiveness of clinical parameters in developing an accurate prognosis.

The assignment of prognosis is one of the most important functions undertaken in clinical practice, yet there is little evidence to support the current decision-making process which is based on an outdated model of disease etiology and progression. This study evaluated 100 treated periodontal patients (2,484 teeth) under maintenance care for 5 years, with 38 of these patients followed for 8 years, to determine the relationship of assigned prognoses to the clinical criteria commonly used in the development of prognosis. The method of generalized estimating equations (GEE) for correlated data was utilized to determine the relationship of each clinical factor to the assignment of initial prognosis, improvement in prognosis at 5 years, and worsening in prognosis at 5 years. A multiple linear regression model was constructed for predicting initial prognosis based on initial clinical data. Increased probing depth, more severe furcation involvement, greater mobility, unsatisfactory crown-to-root ratio, malpositioned teeth, and teeth used as fixed abutments resulted in worse initial prognoses. The coefficients from this model were able to predict accurately the 5-year and 8-year prognoses 81% of the time. When teeth with "good" prognoses were excluded, the predictive accuracy dropped approximately 50%. Multiple logistic regression models indicated that improvement in prognoses and worsening in prognoses were both strongly associated with initial probing depth, initial furcation involvement, initial tooth malposition, and smoking when adjusted for initial prognosis. In addition, good hygiene was found to increase the probability of improvement in prognosis while initial mobility was found to decrease the likelihood of improvement in prognosis. Neither of these factors was found to be significant in worsening of prognosis. Smoking decreased the likelihood of improvement by 60% and doubled the likelihood of worsening in prognosis at 5 years. The results of this study indicate that some clinical factors used in the assignment of prognoses are clearly associated with changes in clinical condition over time. The data also demonstrated that the traditional approach for assigning prognoses is ineffective for teeth with an initial prognosis of less than good. Since most periodontally involved teeth are compromised, further work should include the development of a more effective method for assigning prognoses that is based on clear, objective clinical criteria.

Age Factors↗