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At least 19 recordsLinked to original sources
PubMed1988

[Hormonal contraceptives and cardiovascular risk. Results of an East German multicenter case control study].

Case control studies of oral contraceptives in the literature proved an increasing risk of cardiovascular diseases ranged from 2 to 6. In the presented GDR-case-control-study 425 women with cardiovascular diseases and 1,275 controls without cardiovascular diseases have been entered. Cases and controls were examined in ten centers. We found no elevated risk for ischemic heart disease, cerebrovascular disease, and hypertonic heart disease in oral contraceptive users. The risk did not depend on age, type of oral hormonal contraceptive, and duration of use. There was only a statistical significant increase in the estimated relative risk of 2.05 in venous thrombosis and thrombophlebitis. Of course, prudent medical practice requires that a possible risk of certain cardiovascular events during hormonal contraceptive use must be taken into account when weighting the risks and benefits of each patient's contraceptive choices. Further studies are needed.

Adult↗
PubMed1992

Agreement between oral contraceptive users and prescribers: implications for case-control studies.

Case-control studies examining the effects of oral contraceptives (OC) are prone to misclassification bias due to errors in assessment of OC use. Concern about inaccurate exposure histories has increased since current studies require women to recall OC use over prolonged periods of time. In preparation for a case-control study of breast cancer and OC use, an investigation was carried out to assess agreement between women's lifetime histories of OC use (covering a period of up to 20 years) and prescribers' records. OC histories were obtained during personal interview with 218 women who had used OC at some point in their lives (127 breast cancer patients, 91 controls). Recall was aided by an album with color photographs of all OC marketed in the Netherlands from 1962 onwards (n = 65), and a calendar that covered the women's life span from date of birth to menopause. The participants were asked for the names of all physicians who prescribed OC for them. The rate of response from the prescribers was high (94%), but only half of the forms provided useful information. Patient-prescriber agreement on brand names (including dosage) was 70%. About half of the women agreed with their prescribers on starting dates to within less than a year's difference. Approximately the same percentage of agreement was found for stopping dates. Multiple linear regression indicated that agreement on brand names and dates of usage was lower for women of low socioeconomic status, for healthy women (as compared to breast cancer patients) and for periods of pill use that had to be recalled from the more distant past. Agreement on total duration of use was high enough to permit testing of a moderately strong duration-response relationship in a case-control study.

Adult↗
PubMedDate not supplied

Case-control studies.

Case-control studies investigate associations between exposures to risk factors and a condition of interest. Subjects with the condition (cases) are compared to subjects known not to have the condition (controls) with respect to the presence of risk factors in the past. This design is particularly useful when the condition of interest is relatively uncommon. Case-control studies are useful for studying the etiology of conditions in primary care. Invalid results may be obtained, however, if a study's design allows the occurrence of selection bias, information bias, or confounding.

Case-Control Studies↗
PubMed1992

Risk factors for Alzheimer's disease: the EURODEM collaborative re-analysis of case-control studies.

Case-control studies of risk factors for Alzheimer's disease have been hampered by low statistical power. Here, we present a collaborative analysis of 11 case-control studies of Alzheimer's disease. The original data of these studies were pooled and re-analyzed. The risk factors considered in this analysis were family history of dementia and related disorders, maternal age at index birth, head trauma, medical and psychiatric history and environmental exposures. This paper gives a brief overview of the findings of the re-analysis.

Age Factors↗
PubMed1989

Infant feeding and risk of severe diarrhoea in Basrah city, Iraq: a case-control study.

A case-control study of the relationship between feeding mode and risk of hospitalized diarrhoea in infants (aged 2-11 months) in Basrah city was conducted between September 1983 and May 1984. A total of 597 cases were recruited from among infants admitted with diarrhoea to the major paediatric hospital in the city, while 723 controls were recruited from among healthy infants attending any of the seven maternal and child health clinics in Basrah. A variety of potentially confounding variables were controlled in the analysis. For infants aged 2-5 months, breast-feeding alone or breast-feeding plus food were the least risky feeding modes. Bottle-feeding was dangerous and bottle-feeding alone was associated with a risk of 55 among infants aged 2-3 months, and 37 among infants aged 4-5 months, relative to exclusive breast-feeding. For older infants (6-11 months), the risks of hospitalized diarrhoea were not significantly different among different partial breast-feeding modes, but non-breastfeeding was dangerous, especially exclusive bottle-feeding. Food intake was associated with a reduced risk of severe diarrhoea among bottle-fed infants but not with an increased risk among breast-fed infants. Among bottle-fed infants, no association was found between risk of severe diarrhoea and method of bottle-cleaning. Previous breast-feeding conferred no current protection.

Bottle Feeding↗
PubMed1992

Pelvic surgery, reproductive factors and risk of ectopic pregnancy: a case controlled study.

A case controlled study among 361 women with surgically treated ectopic pregnancy and 420 women delivered at term was designed, aiming at characterization of the association among previous pelvic operations, selected reproductive factors and ectopic pregnancy. All types of previous pelvic operations increase the risk of ectopic pregnancy from a 2-fold increase for appendectomy to a 9-fold increase for ectopic pregnancy, if maternal age, parity, history of spontaneous and induced abortions and history of infertility is controlled. This study suggests that a previous pelvic operation may increase the risk of ectopic pregnancy.

Abortion, Induced↗
PubMed1992

Transient global amnesia. A case control study.

A case control study of transient global amnesia (TGA), transient ischaemic attacks (TIA) and normal controls is described. Each of the 51 TGA patients, selected between January 1985 and March 1990, was compared with four controls (two TIAs and two normals) for the presence of vascular risk factors (hypertension, diabetes, smoking habits, cholesterol, triglycerides and haematocrit levels, heart disease, previous stroke), previous TGA, migraine, psychiatric illness and recent head trauma. Patients with TGA had less diabetes, hypercholesterolaemia and hypertriglyceridaemia than TIA. TGA subjects had significantly more hypertension (odds ratio = 3.31) and migraine (odds ratio = 8.67) than normal controls. During a mean of 17.4 mths of follow-up (range 1-96 mths), three subjects had recurrent TGA, one sustained a TIA and a minor stroke, but none had seizures. Thrombo-embolism and epilepsy are unlikely to be the cause of this benign disorder. The role is stressed of appropriate precipitants, including haemodynamic changes, and of individual susceptibility (of which migraine is probably a marker) in the genesis of TGA.

Adult↗
PubMedDate not supplied

Risk factors for febrile seizures in the People's Republic of China: a case control study.

A case control study was conducted to investigate the association of family history of febrile seizures (FS) and history of maternal, pregnancy and delivery, and postnatal factors with FS. Information was gathered by door-to-door survey in six major cities in the People's Republic of China. Factors present before the date of onset of FS were assessed in 182 subjects and in an equal number of controls matched for age, sex, and geographic area. The odds ratio for risk of FS in children with a family history of FS in a first-degree relative was 10.0 (confidence interval 2.7-58.6), confirming other observations that familial factors are an important predisposing characteristic for FS. Maternal acute respiratory infection during the first trimester of pregnancy was slightly more frequent in children with FS (odds ratio, 1.9 confidence interval 1.0-3.9). None of the other examined pregnancy or delivery factors was associated with an increased risk, suggesting that birth history is not an important factor predisposing to FS.

Adolescent↗
PubMed1991

Familial aggregation of Alzheimer's disease and related disorders: a collaborative re-analysis of case-control studies.

Case-control studies of Alzheimer's disease were re-analysed to examine the association of Alzheimer's disease with family history in first degree relatives of dementia, Down's syndrome and Parkinson's disease. Overall, the relative risk of Alzheimer's disease for those with at least one first degree relative with dementia was 3.5 (95% confidence interval 2.6-4.6). Stratification according to age of onset of Alzheimer's disease showed that the relative risk decreased with increasing onset age. However, among patients with an onset of disease after 80 years, there were still significantly more subjects with one or more first degree relatives with dementia as compared to controls (relative risk 2.6; 95% confidence interval 1.3-5.2). The relative risk of Alzheimer's disease was significantly lower in patients who had one first degree relative with dementia (relative risk 2.6; 95% confidence interval 2.0-3.5) as compared to those who had two or more affected relatives (relative risk 7.5; 95% confidence interval 3.3-16.7). Furthermore, the re-analysis showed a significant association between Alzheimer's disease and family history of Down's syndrome (relative risk 2.7; 95% confidence interval 1.2-5.7), which was strongest in those patients who had a positive family history of dementia. The relative risk of Alzheimer's disease for those with a positive family history of Parkinson's disease was 2.4 (95% confidence interval 1.0-5.8).

Age Factors↗
PubMed1990

[Experimental study and case control study of nosocomial infection caused by Pseudomonas aeruginosa].

144 strains of Pseudomonas aeruginosa (Ps.a) were serotyped and phage-typed. Antibiotic sensitivity test and case control study of nosocomial infection caused by Ps.a were also done for these strains. Three epidemic strains were collected from the ICU in a neurosurgical ward. The etiology of a cross infection among tracheotomy patients was two epidemic strains isolated from the hands of a nurse and an attendant. Hospitalization days longer than 56 days, tracheotomy and indwelling catheterization were 3 risk factors for Ps.a infection shown by logistic analysis. The sensitivity rate of Ps.a to antibiotics was highest with ceftazidine, followed by amikacin and piperacillin. The most common resistant antibiogram was Gentamycin and tobramycin Resistance to gentamicin increased obviously.

Aged↗
PubMed1991

Human papillomavirus infection and other risk factors for cervical neoplasia: a case-control study.

A case control design has been used to investigate risk factors associated with the development of cervical squamous intraepithelial lesions (SIL) in a population of urban women in which non-affluent minority groups were heavily represented. Eighty-five women with histologically confirmed SIL were compared to a control group of 70 cytologically normal women. HPV infection was determined using both Southern blot hybridization and polymerase chain reaction (PCR) amplification specific for HPV types 16, 18, and 33. When Southern blot was used to detect HPV, logistic regression analysis identified HPV infection (odds ratio (OR) = 17.9, 95% confidence interval (CI) = 6.2-51.6) and low educational achievement (OR = 3.4, 95% CI = 1.2-10.1) as major independent risk factors. When PCR was employed to detect HPV, the logistic regression model suggested that HPV infection (OR = 10.4, 95% CI = 3.6-30.4) and Hispanic ethnicity (OR = 5.0, 95% CI = 1.2-20.5) represented independent risk factors; low educational achievement and Black ethnicity were risk factors of borderline significance. PCR detection of simultaneous co-infection with more than one HPV type was associated with a very high risk of SIL (OR for one type = 7.2, 95% CI = 2.4-21.9; OR for greater than I type = 43.0, 95% CI = 6.9-266.6). Furthermore, increased viral load determined by either method carried an increased risk of disease. HPV infection with viral types previously reported to be related to neoplastic or dysplastic lesions carried the highest risk of SIL. The association of HPV detected by Southern blot and SIL in women less than 35 years old had an OR of 10.1, whereas in women greater than or equal to 35 the OR was 74.5 (p = 0.09 for homogeneity of ORs). We conclude that infection with HPV is the major risk factor for cervical SIL and suggest that targeted HPV screening of women over age 35 may represent an innovative strategy to detect women at high risk of cervical neoplasia.

Age Factors↗
PubMed1991

[Sinonasal cancer and occupation: a multicenter case-control study].

A case-control study was conducted to examine occupational risk factors for sinonasal cancer. 207 cases and 409 controls (323 cancer hospital controls and 86 controls selected from lists provided by the cases) were included in the study. All cases and controls were interviewed by specially trained physicians. Detailed information on occupational history was collected, in addition to other potential risk factors for nasal cancer. Results are presented for two histologic types: adenocarcinoma and squamous cell carcinoma. Among males, the risk of adenocarcinoma was significantly elevated for carpenter and joiners (OR = 17.7) and other woodworkers (OR = 26.9). A significant increase in risk of squamous cell cancer (OR = 2.5) and a moderate increase in risk of adenocarcinoma (OR = 1.7; NS) were noted for construction workers. Among females, an excess risk of squamous cell carcinoma was associated with employment in textile industry (OR = 2.9). Elevated risks of squamous cell cancer were observed for farm workers of both sexes (males: OR = 2.2; females OR = 4.9).

Adenocarcinoma↗
PubMed1992

Risk factors for fatal venous thromboembolism in young women: a case-control study.

A case-control study of fatal venous thromboembolism in young women is described. Sixty women aged between 16 and 39 who died from thromboembolism in England and Wales between 1986 and 1988 were included in the study. Two living controls matched for age and marital status were sought from the records of the general practitioner with whom each case was registered. Some 115 controls were included in the study. The cases had a significantly higher prevalence of a history of major illness, particularly thrombotic episodes, than the controls. The odds ratio (OR) of a fatal thromboembolism in women who had a history of venous thrombosis was 4.0 (95% Cl: 1.4-11.5). There was also a significantly higher frequency of a recent operation or accident amongst the cases than the controls (OR = 11.1, 95% Cl: 1.3-92.5). There was no significant excess or oral contraceptive use amongst the cases. The overall OR associated with current use of oral contraceptives was 1.6 (95% Cl: 0.7-3.4), while the corresponding OR for 'idiopathic' diseases was 2.1 (95% Cl: 0.8-5.2). These risks are considerably smaller than those observed in previous studies. The observed risk may be low because the dosage of oestrogen in modern oral contraceptive preparations has been reduced, but it may also be because the cases of fatal venous thromboembolism included in this study represent only a small proportion of all cases of venous thrombeombolism; a disease which is rarely fatal in young women. These results cannot necessarily be extrapolated to nonfatal venous thromboembolism.

Adolescent↗
PubMed1992

Fatal stroke and use of oral contraceptives: findings from a case-control study.

A case-control study of women less than 40 years of age in England and Wales was performed to evaluate the risk of fatal stroke associated with the use of the newer, low-dose oral contraceptives. Included were 296 cases with subarachnoid hemorrhage, 105 cases with other hemorrhagic stroke, and 21 cases with occlusive stroke, all of which occurred during 1986-1988. Two living controls per case, matched for age and marital status, were chosen from the general practice lists. The power of the study was such that the minimum significant increased relative risk of subarachnoid hemorrhage associated with ever having used oral contraceptives that could have been detected with 90% certainty was 1.6; the equivalent value for occlusive stroke was 28.4. Relative risk was estimated by conditional logistic regression allowing for matching. The adjusted relative risk of subarachnoid hemorrhage associated with oral contraceptives was estimated to be 1.1 (95% confidence interval (CI) 0.6-1.9) for current use and 1.3 (95% CI 0.9-1.8) for ever use, while the equivalent relative risk of an occlusive stroke associated with ever use was 4.4 (95% CI 0.8-24.4). Oral contraceptive use may be associated with a small increase in the risk of subarachnoid hemorrhage. These data are consistent with a substantial increase in the risk of occlusive stroke associated with oral contraceptive use.

Adolescent↗
PubMed1989

Occupation and bladder cancer in Spain: a multi-centre case-control study.

A case-control study on bladder cancer was carried out in four regions of Spain. The study included 497 cases (438 males and 59 females), 583 hospital controls and 530 population controls matched by sex, age and residence. The present paper reports the results of the analyses on occupational history. Among men, an increased risk of bladder cancer was found for textile workers (OR = 1.97, 95% CL 1.2-3.3), mechanics and maintenance workers (OR = 1.86, 95% CL 1.2-2.8), workers in the printing industry (OR = 2.06, 95% CL 1.0-4.3) and for managers (OR = 2.03, 95% CL 1.2-3.5). The risk was highest among those first employed in the textile industry before the age of 25 and prior to 1960. Among mechanics the risk was highest for those who started after the age of 25 and later than 1960. The OR for smokers who had also been employed in one of the high risk occupations was 7.82 (95% CL 4.4-14.0) which is compatible with a multiplicative effect of joint exposure to tobacco and occupational hazards.

Aged↗
PubMed1990

Rotavirus diarrhoea in Apache children: a case-control study.

A case-control study of rotavirus diarrhoea in Apache children up to two years old was conducted at the White Mountain Apache reservation from 1 May through 15 December 1985 to identify risk factors for rotavirus diarrhoea. The mothers of fifty cases, forty-five hospital controls and twenty-five neighbourhood controls participated in this study. Exposure to other children with diarrhoea stood out as the single most important factor for acquiring rotavirus diarrhoea (Odds ratio = 14.0). Other significant risk factors were living in homes with septic tanks and in homes with 'poor environmental sanitation.'. Minimizing contacts of children with diarrhoea therefore would be the most effective measure in preventing the spread of this disease in the community.

Arizona↗