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PubMedDate not supplied

Do depressive symptoms predict declines in physical performance in an elderly, biracial population?

OBJECTIVE: We investigated whether depressive symptoms, assessed by the 10-item Center for Epidemiological Studies Depression Scale (CES-D), predicted change in physical function in elderly adults. METHODS: Participants were from a biracial, population-based sample of adults aged 65 and older (N: 4069; 61% black; 61% female). Physical function was assessed as a summary performance measure of tandem stand, measured walk, and repeated chair stand (mean [standard deviation], 10.3 [3.5]; range, 0-15), commonly used measures of overall physical health in older adults. Generalized estimating equation models estimated physical function across 3 assessments over 5.4 years of follow up as a function of CES-D scores at baseline. RESULTS: Adjusting for age, sex, race, and education, each 1-point higher CES-D score was associated with a 0.34-point lower absolute level of physical performance (p < .0001), but there was no evidence of a CES-D by time interaction (p = .84), indicating that depressive symptoms at baseline were not associated with greater physical performance decline over time. In secondary analyses, with CES-D scores modeled in 4 categories, overall physical performance showed a graded, inverse association across CES-D categories (p's < .0001). However, we observed no threshold effect for depressive symptoms in relation to change in physical performance. Compared with the referent group (CES-D = 0), the 2 middle CES-D categories (CES-D = 1 or 2-3) evidenced some decline in physical performance over time, but the highest CES-D group (CES-D > or =4) showed no significant physical decline over time (p = .89). CONCLUSION: We observed a strong cross-sectional association between depressive symptoms and overall physical performance. Physical function declined over time, yet depressive symptoms did not consistently contribute to greater decline over an average of 5.4 years of follow up among older adults. Findings highlight the importance of longitudinal models in understanding the relation between depressive symptomatology and physical health.

Age Factors↗
PubMed1993

Cell-specific physical and functional coupling of human 5-HT1A receptors to inhibitory G protein alpha-subunits and lack of coupling to Gs alpha.

We have studied the physical and functional linkages of heterologously expressed human 5-HT1A receptors to G protein alpha-subunits in HeLa and CHO-K1 cells. HeLa cells expressed immunoreactivity to G(i) proteins with an apparent rank order of G(i) alpha 3 (approximately 1 pmol/mg of protein) >> G(i) alpha 1 (approximately 0.1 pmol/mg) >> G(i) alpha 2 (< 0.02 pmol/mg), whereas CHO-K1 cells expressed immunoreactivity to G(i) alpha 2 (approximately 5 pmol/mg) >> G(i) alpha 3 (approximately 0.7 pmol/mg), but not to G(i) alpha 1. Both cell lines expressed large and small forms of Gs alpha, but neither expressed detectable G(o) alpha. Agonist-promotable physical coupling of the 5-HT1A receptor to G proteins was examined with high-affinity agonist binding and with co-immunoprecipitation using rabbit anti-receptor IgG fractions. Agonist treatment induced coupling of the 5-HT1A receptors to G proteins with an apparent rank order of G(i) alpha 3 > G(i) alpha 1, G(i) alpha 2 in HeLa cells and G(i) alpha 3 > G(i) alpha 2 in CHO-K1 cells. Agonist-promotable functional coupling of the 5-HT1A receptors to inhibition of adenylylcyclase was measured in membranes derived from HeLa and CHO-K1 cells expressing approximately 2.5-3 pmol of receptors/mg of protein by preincubation with antisera raised against the carboxyl termini of the G(i) protein alpha-subunits. A noteworthy difference between the two cell types was that antisera against the predominant G protein (G(i) alpha 2) were substantially more efficacious than G(i) alpha 3 antisera at blocking functional coupling to adenylylcyclase inhibition in CHO-K1 cells, whereas in HeLa cells, antisera against nonpredominant G proteins (G(i) alpha 1/G(i) alpha 2) were equally as effective as those against the predominant G protein (G(i) alpha 3). No physical or functional coupling of the 5-HT1A receptor to Gs alpha isoforms was detected in either cell line. These findings suggest that the 5-HT1A receptor can physically couple to multiple distinct G(i) proteins in mammalian cell membranes and that functional coupling to adenylylcyclase inhibition may be mediated by G(i) alpha 1, G(i) alpha 2, and G(i) alpha 3. One factor influencing the relative importance of those G proteins for 5-HT1A receptor-inhibited adenylylcyclase activity appears to be their-relative levels of expression.(ABSTRACT TRUNCATED AT 250 WORDS)

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed2001

Electrophysiological assessments of primitive reflexes in stroke patients.

OBJECTIVE: To evaluate the primitive reflexes by electrophysiological assessments and their correlation with the cognitive and physical functioning of stroke patients. METHODS: Electrophysiological studies of primitive reflexes including jaw jerk, snout reflex, glabellar reflex, and corneomandibular reflexes were performed in 38 stroke patients and 26 normal controls. Cognitive function of patients was assessed by Modified Mini-Mental State (3MS) Examination and logical memory test. The Chinese Functional Independence Scale (CFIS) was used to evaluate the physical functioning and social domains of stroke patients. RESULTS: The presence rate of primitive reflexes was higher in stroke patients than in normal controls. Wave amplitude of snout and corneomandibular reflexes obtained from stroke patients was greater than those from controls. No definite difference in reflex conduction latencies was observed between the two groups. A regression relationship was noted between the wave amplitude of snout reflexes and the 3MS and CFIS scores of stroke patients. CONCLUSION: Primitive reflexes can be measured by electrophysiological assessments. The results may serve as an objective and useful parameter in evaluation of cognition and physical functioning of stroke patients.

Aged↗
PubMed1991

Relationships between lung function and physical characteristics in young adult black and white males and females.

The relationships of lung function to physical characteristics in young adults have not been adequately described for different gender-race groups in the United States. As part of a study of the effects of ozone exposure upon Black and White men and women, we measured lung volumes, expiratory flow rates, and airways resistance on a sample of 314 healthy 18-35 yr old nonsmokers. Regression analysis indicated that lung function was adequately described as a linear function of either height or sitting height in each of the four groups, and that while not always significant, gender and race differences in the height and sitting height coefficients were consistently present with those of males and Whites larger than those of females and Blacks, respectively. Lung volumes were frequently observed to be associated with body mass index as measured by Quetelet Index (weight.height.2). The best fitting gender-race specific multiple regression models including these terms and occasional age terms are presented. Two additional models are presented, one of which simultaneously adjusts for both gender and race, and the other of which adjusts for gender for a given race. Comparison of predicted values from our study to those of other studies suggests that the population samples from this study may be similar to those of other American populations reported upon by others.

Adolescent↗
PubMed2001

Self-reported preclinical disability identifies older women with early declines in performance and early disease.

There appears to be a preclinical stage of physical disability which precedes onset of task difficulty (disability) in those who develop disability progressively as a result of chronic disease. Such a stage provides a basis for identifying older adults at risk of becoming disabled. This cross-sectional study evaluated whether a preclinical stage of physical function identified by self-report is associated with decrements in objective physical performance measures or increases in disease; that is, whether these measures, in those with preclinical disability, are intermediate between individuals who report no difficulty and no preclinical changes and those who report difficulty. The Women's Health and Aging Study II, an observational study of 436 women 70-80 years of age who were among the two-thirds least disabled living in the community. Participants were sampled from the HCFA Medicare eligibility lists and were determined eligible if they reported no difficulty, or difficulty in only one of four domains of physical function: mobility, upper extremity, IADL and ADL tasks. At the first follow-up (18 months after baseline), participants completed questionnaires on physical functioning for tasks in each of these domains, with possible answer options for each task: they had (1) difficulty (disabled); (2) no difficulty and no modification of task performance (High Function); or (3) no difficulty but reported modification and/or change in frequency of task performance (a self-report measure of preclinical disability predictive of incident difficulty). At the same visit, standardized, objective measures of function and disease were obtained, including measured walk; chair stands; strength: hip flexion, knee extension, ankle dorsiflexion, and grip; balance: function reach, single leg stand, tandem stand; joint exam: hip pain on passive motion and knee pain or tenderness; spirometry; ankle:arm blood pressure ratio; visual function: acuity, contrast sensitivity, stereopsis; and graded treadmill exercise test. Data were analyzed from the first follow-up examination. Physical performance decreased, and disease frequency increased, in association with decreasing self-reported mobility function (in walking one-half mile and climbing 10 steps), across three self-report categories: High Function, Preclinical Disability (Task Modification but No Difficulty) and Disability (Difficulty). These findings pertained for measures of walking speed, balance, strength, and knee and hip osteoarthritis. Self-reported level of function predicted differences in ranges as well as means for walking speed, balance and strength. These findings indicate a physiologic basis for self-reported function, including preclinical disability, specifically that different levels of disease severity, impairments and physical performance are concurrently associated with different categories of self-reported function. They also suggest new avenues for screening and intervention to prevent disability.

Aged↗
PubMed2005

How does quality of life of patients with systemic lupus erythematosus compare with that of other common chronic illnesses?

OBJECTIVE: Comparison of health related quality of life (HRQOL) of patients with systemic lupus erythematosus (SLE) with other common chronic illnesses. METHODS: Responses from self-administered Medical Outcomes Study Short Form-36 (SF-36) questionnaires from 90 patients with SLE, recorded in the lupus database at the University of Chicago Hospital, were analyzed. Comparative norms and domain scores for patients with other chronic diseases [hypertension, congestive heart failure (CHF), adult onset diabetes mellitus, myocardial infarction, and depression] were used and are based on the general US population. T tests were used to make comparisons. RESULTS: Patients with SLE were younger than patients with most reference chronic conditions except for depression. Their Physical Component Scores and Mental Component Scores were 30 +/- 10.5 and 45.1 +/- 11, respectively. SLE patients fared significantly worse than age matched norms from the general US population for women (p = 0.0001) in all 8 domains. Their quality of life was significantly worse than for those with hypertension, diabetes, or myocardial infarction in all domains (p < 0.004). Patients with CHF were no worse than those with SLE in regard to physical function, role-physical, role-emotional, and vitality. CHF patients fared significantly better in mental health, bodily pain, social functioning, and general health, compared to patients with SLE. Patients with depression were significantly impaired in role-emotional and mental health domains (p = 0.0001) compared to SLE patients, but were no worse (role-physical, vitality, and social functioning) and even better (physical function, bodily pain, and general health) in some. General health of SLE patients was significantly lower than all comparative groups. CONCLUSION: HRQOL of patients with SLE seems to be significantly worse and affects all health domains at an earlier age in comparison to patients with some other common chronic diseases.

Adaptation, Psychological↗
PubMed2003

Is retirement good or bad for mental and physical health functioning? Whitehall II longitudinal study of civil servants.

BACKGROUND: To determine whether retirement at age 60 is associated with improvement or deterioration in mental and physical health, when analysed by occupational grade and gender. METHODS: Longitudinal study of civil servants aged 54 to 59 years at baseline, comparing changes in SF-36 health functioning in retired (n=392) and working (n=618) participants at follow up. Data were collected from self completed questionnaires. RESULTS: Mental health functioning deteriorated among those who continued to work, but improved among the retired. However, improvements in mental health were restricted to those in higher employment grades. Physical functioning declined in both working and retired civil servants. CONCLUSION: The study found that retirement at age 60 had no effects on physical health functioning and, if anything, was associated with an improvement in mental health, particularly among high socioeconomic status groups.

Female↗
PubMed1989

Determinants of recovery 12 months after hip fracture: the importance of psychosocial factors.

The independent contributions to recovery from hip fracture of psychosocial factors including depression, personality, social connectedness, and self-rated health were studied in 219 women age 59 and older (mean age 78.5) who were community dwelling prior to fracture. Initial assessments were conducted shortly after surgery and follow up assessments 2, 6, and 12 months later. By 12 months, 15 patients had died and 15 had entered a nursing home. Substantial declines in physical functioning though not psychosocial status were observed. Only 21 per cent (compared to 81 per cent prefracture) reported walking independently; fewer than 30 per cent had regained reported prefracture levels of physical function. The proportion with elevated depression scores at 12 months was 20 per cent, down from 51 per cent following surgery; 64 per cent rated their health excellent or good at 12 months, up from 43 per cent after surgery. Poor cognitive status and post-surgical self-rated health were predictive of mortality. Among survivors, age, prefracture physical functioning, and cognitive status were associated with recovery in physical function but not psychosocial status. High post-surgery depression scores, but not the other psychosocial factors, were associated with poorer recovery in both functional and psychosocial status. These findings demonstrate the importance of depressive symptoms as one determinant of recovery from hip fracture and support the need to attend to the affective status of hip fracture patients following surgery.

Aged↗
PubMed2006

Effects of resistance exercise training and nandrolone decanoate on body composition and muscle function among patients who receive hemodialysis: A randomized, controlled trial.

Patients who are on hemodialysis commonly experience muscle wasting and weakness, which have a negative effect on physical functioning and quality of life. The objective of this study was to determine whether anabolic steroid administration and resistance exercise training induce anabolic effects among patients who receive maintenance hemodialysis. A randomized 2 x 2 factorial trial of anabolic steroid administration and resistance exercise training was conducted in 79 patients who were receiving maintenance hemodialysis at University of California, San Francisco-affiliated dialysis units. Interventions included double-blinded weekly nandrolone decanoate (100 mg for women; 200 mg for men) or placebo injections and lower extremity resistance exercise training for 12 wk during hemodialysis sessions three times per week using ankle weights. Primary outcomes included change in lean body mass (LBM) measured by dual-energy x-ray absorptiometry, quadriceps muscle cross-sectional area measured by magnetic resonance imaging, and knee extensor muscle strength. Secondary outcomes included changes in physical performance, self-reported physical functioning, and physical activity. Sixty-eight patients completed the study. Patients who received nandrolone decanoate increased their LBM by 3.1 +/- 2.2 kg (P < 0.0001). Exercise did not result in a significant increase in LBM. Quadriceps muscle cross-sectional area increased in patients who were assigned to exercise (P = 0.01) and to nandrolone (P < 0.0001) in an additive manner. Patients who exercised increased their strength in a training-specific fashion, and exercise was associated with an improvement in self-reported physical functioning (P = 0.04 compared with nonexercising groups). Nandrolone decanoate and resistance exercise produced anabolic effects among patients who were on hemodialysis. Further studies are needed to determine whether these interventions improve survival.

Absorptiometry, Photon↗
PubMedDate not supplied

Gender differences in the health related quality of life of older adults with heart failure.

OBJECTIVE: The objective of this study was to explore whether gender differences exist in health-related quality of life for older adult men and women with heart failure. DESIGN: A secondary data analysis was conducted on an existing dataset of heart failure patients. The original study used an exploratory, correlational longitudinal design. SUBJECTS: 138 subjects (69 men and 69 women) with heart failure completed both data points of the study. RESULTS: Men and women were similar on the number and types of heart failure-related symptoms they experienced. Twenty-seven percent of the subjects could be classified as depressed. The men had better physical functioning than the women did with gender making a greater contribution to physical functioning than age or marital status. Twenty-three percent of the subjects were rehospitalized 4 to 6 weeks after the initial hospital discharge. CONCLUSIONS: This study showed that the health related quality of life for older men and women with heart failure is significantly impacted by heart failure. Older men and women have similar heart failure symptoms, depression, and rehospitalization following a hospital admission for heart failure. Both older men and older women with heart failure have impairments in their physical functioning with older women more physically impaired than older men.

Aged↗
PubMed2000

Correlates of delayed referral for the diagnosis of dementia in an outpatient population.

BACKGROUND: Early diagnosis of dementia is critical, but there is usually a time lag between onset of symptoms and referral for neuropsychological testing and dementia diagnosis. We aimed to identify factors correlated with this delayed referral. METHODS: We studied 140 patients with cognitive deterioration referred to the Memory Clinic of the Catholic University (Rome) between 1995 and 1996. Alzheimer's disease or multi-infarct dementia was diagnosed according to National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria and Hachinski ischemic score. Global cognitive and neuropsychological functions were assessed with the Mini-Mental State Exam (MMSE) and the Mental Deterioration Battery. The performance on the Activities of Daily Living was used to measure physical function. The time between onset of signs of cognitive deterioration and referral for diagnosis (time to diagnosis: TTD) was estimated through a semistructured interview of the caregiver. Independent correlates of TTD were identified after adjustment for potential confounders and stratifying patients based on level of physical function. RESULTS: Of 127 eligible patients, 63% had Alzheimer's disease, 26% multi-infarct dementia, and 11% had dementia of other types. Mean age was 73.9 +/- 8.2 years, and 59% of patients were females. The mean TTD was 13.8 +/- 10.8 months and did not differ by gender, household composition, or type of dementia. For patients with normal physical function, increased age (beta = .50), female sex (beta = .51), and low MMSE score (beta = .36) were associated with longer TTD. Among patients with physical impairment, only MMSE score showed an association with TTD, but it was of opposite direction (beta = -.31). These associations were consistent by type of dementia. CONCLUSIONS: Age, gender, and degree of cognitive impairment are important correlates of the time between onset of signs/symptoms and referral for dementia diagnosis. These factors are independent of the type of dementia but are influenced by the level of physical function.

Activities of Daily Living↗
PubMed2005

Prevalence and impact on generic quality of life of urinary incontinence in Japanese working women: assessment by ICI questionnaire and SF-36 Health Survey.

OBJECTIVES: To examine the prevalence of urinary incontinence (UI) and the relationship between UI and generic quality of life (QOL) in working women. METHODS: Of 7229 female hospital nurses in Japan, 3734 (51.7%) responded to a self-administered postal questionnaire that included the Rand Medical Outcomes Study 36-item Health Survey (SF-36) and the International Consultation on Incontinence questionnaire (ICIQ) for evaluating symptoms and health-related QOL. RESULTS: The overall prevalence of UI in Japanese working women aged 20 to 64 years (mean 35.2) was 16.7%. The main type of incontinence was stress UI (73%). Its prevalence increased with age and reached a plateau at age 45 to 49 years (34.7%). The ICIQ score also correlated significantly with age. Generic QOL, especially physical functioning, role-physical, social functioning, and role-emotional, was significantly impaired by UI. A comparison of subjects with and without UI revealed that the differences in the physical and mental component summary scores of the SF-36 were largest in the age groups of 25 to 29 and 55 to 59 years, respectively. The correlations of the ICIQ score with the physical and mental component scores were most significant in the age groups of 25 to 29 and 45 to 49 years, respectively. The impact of mixed UI on QOL showed a greater tendency than that of stress or urge UI. CONCLUSIONS: The prevalence of UI showed an age-related increase, with a peak at 45 to 49 years old. The impact of UI on physical health was great in individuals in their 20s, but its impact on mental health increased in the older age groups.

Adult↗
PubMed2007

Active lifestyle protects against incident low back pain in seniors: a population-based 2-year prospective study of 1387 Danish twins aged 70-100 years.

STUDY DESIGN: Prospective cohort study of twins. OBJECTIVES: To investigate associations between physical activity, physical function, and incident low back pain (LBP) in an elderly population. SUMMARY OF BACKGROUND DATA: The relationship between an active lifestyle and LBP in seniors is unknown. METHODS: Participants in the population-based Longitudinal Study of Aging Danish Twins free from LBP at baseline (no LBP during the past month) were included, and interview data on physical activity, overall physical function, and LBP at baseline and follow-up were obtained. Associations between levels of physical activity and LBP were estimated using logistic regression for the entire cohort, and using a matched case-control design for twin pairs discordant for physical activity. Absolute risk and relative risks for incident LBP in relation to physical activity were calculated for participants with higher or lower than average physical function at baseline. Absolute risk for LBP was also calculated for participants based on whether they remained active or inactive between baseline and follow-up or changed activity level. RESULTS: A total of 1387 persons aged 70-100 at baseline were included in the analyses, including 86 twin pairs discordant for physical activity at baseline. In the total sample, 83% were engaged in light physical activity, and 42% of men and 35% of women were engaged in strenuous physical activity at least weekly. Being engaged in strenuous physical activity at baseline was strongly protective in relation to both having had any LBP (odds ratio 0.21, 95% confidence interval 0.12-0.37 for intra-pair analysis) and having had LBP lasting more than 30 days altogether during the past year at follow-up (odds ratio 0.08, 95% confidence interval 0.03-0.18 for intra-pair analysis). Statistically significant dose-response associations between increasing frequency of strenuous physical activity and magnitude of this protective effect were found. Participants with poor initial physical function experienced the strongest protective effect of strenuous physical activity. Finally, LBP does not appear to be an important factor affecting whether participants remained engaged in strenuous physical activity at baseline and follow-up or vice versa. CONCLUSIONS: Strenuous physical activity at least once a week is protective for incident LBP in seniors.

Aged↗
PubMed2006

[Development of a rating scale for self-efficacy of physical activity in frail elderly people].

AIM: The purpose of the present study was to 1) development the scale of the self-efficacy of physical activity in frail elderly people (SEPAF), 2) investigate the relationship of physical functions and instrumental activity of daily living (IADL). METHODS: The study included 187 community-dwelling elderly people. Subject's SEPAF (walking, stair-climbing, lifting a weight), physical functions (usual gait speed, maximum gait speed, knee extension muscle strength, hand grip) and IADL according to the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG Index of Competence) were measured. The reliability of this scale was examined using Cronbach's alpha, and test-retest correlation. The criterion-related validity and the construct validity were evaluated relatively using physical functions and factor analysis. The score was compared between young-old and old-old and gender. The correlation between SEPAF and TMIG Index of Competence was examined. RESULTS: Cronbach's a showing internal consistency for these scales were 0.78-0.82. The score showed significant differences in gender and age group. There were significant relationships between SEPAF and physical functions, and the TMIG Index of Competence. CONCLUSION: The SEPAF was shown to be highly reliable. Few scale for frail elderly people exist, and it is useful to assess the self-efficacy of physical activities in frail and community-dwelling elderly people.

Activities of Daily Living↗
PubMed2000

The relationship between alcohol problems and health functioning of older adults in primary care settings.

OBJECTIVE: The purpose of this study was to determine the relationship between alcohol use and health functioning in a sample of older adults screened in primary care settings. DESIGN: A cross-sectional study. SETTING: Thirty-seven primary care clinics. PARTICIPANTS: Older adults (n = 8,578; aged 55-97) with regularly scheduled appointments in primary care clinics were screened. MEASUREMENTS: Participants were categorized based on alcohol consumption levels as abstainers, low-risk drinkers, and at-risk drinkers (women: 9 or more drinks/week; men: 12 or more drinks/week). Dependent variables were eight SF-36 health functioning scales. RESULTS: Sixty-one percent of participants were abstainers, 31% were low-risk drinkers, and 7% were at-risk drinkers. ANCOVAs found significant effects of drinking status on General Health, Physical Functioning, Physical Role Functioning, Bodily Pain, Vitality, Mental Health, Emotional Role, and Social Functioning, controlling for age and gender, with low-risk drinkers scoring significantly better than abstainers. At-risk drinkers had significantly poorer mental health functioning than low-risk drinkers. Few significant gender differences were found on SF-36 scales. CONCLUSIONS: Older adults who are at-risk drinkers may not present with poor physical health functioning. Future studies are needed to determine the relationship between drinking limits for older adults and other areas of physical and psychosocial health.

Activities of Daily Living↗
PubMed2003

Evolutionary conservation of physical and functional interactions between phospholipase D and actin.

Phospholipase D (PLD) enzymes from bacteria to mammals exhibit a highly conserved core structure and catalytic mechanism, but whether protein-protein interactions exhibit similar commonality is unknown. Our objective was to determine whether the physical and functional interactions of mammalian PLDs with actin are evolutionarily conserved among bacterial and plant PLDs. Highly purified bacterial and plant PLDs cosedimented with mammalian skeletal muscle alpha-actin, indicating direct interaction with F-actin. The binding of bacterial PLD to G-actin exhibited two affinity states, with dissociation constants of 1.13 pM and 0.58 microM. The effects of actin on the activities of bacterial and plant PLDs were polymerization dependent; monomeric G-actin inhibited PLD activity, whereas polymerized F-actin augmented PLD activity. Actin modulation of bacterial and plant PLDs demonstrated kinetic characteristics, efficacies, and potencies similar to those of human PLD1. Thus, physical and functional interactions between PLD and actin in PLD family members from bacteria to mammals are highly conserved throughout evolution.

Actins↗
PubMed2004

Instrumental variables technique: cigarette price provided better estimate of effects of smoking on SF-12.

OBJECTIVE: Debate surrounds the usefulness of the instrumental variables (IV) technique for medical research. The choice of an instrument for the technique has been contentious. This study estimated the effects of smoking on physical functional status. We chose an especially valid and strong instrument: cigarette price. STUDY DESIGN AND SETTING: The data were a nationally representative cross-sectional sample of 34,288 persons aged 30 to 91 in 1996-1997. The sample was drawn from the Community Tracking Study. Number of cigarettes smoked per day was predicted by the average cigarette price for the state in which the subject resided. The outcome measure was physical functional status and was measured by the SF-12 physical functional index. RESULTS: In multivariable models we found the following: cigarettes per day was strongly and negatively associated with the SF-12 index (P<.001); cigarette price was strongly and negatively associated with cigarettes per day (P=.002); the predicted cigarettes per day (the IV) was strongly and negatively associated with the SF-12 index in linear regression and tobit regression (P=.047 and P=.021). CONCLUSION: Estimated coefficients from the IV method suggested that the effect of smoking on physical functional status was substantially larger than estimates that relied on conventional methods.

Adult↗