Alcohol consumption and erectile dysfunction: meta-analysis of population-based studies.

Alcohol is long regarded as a risk factor for erectile dysfunction (ED), but epidemiological evidence has been equivocal. We aimed to investigate the ED risk associated with various levels of alcohol consumption by meta-analysis. We searched for population-based studies on ED through Medline, PubMed, PsychInfo, and scanned through reference lists. Eleven cross-sectional studies were included and analyzed with random effects model. We reviewed the results from one cross-sectional study and two cohort studies. Regular alcohol consumption was negatively associated with ED (odds ratio (OR)=0.79; 99% confidence interval (CI), 0.67-0.92; P<0.001). Consumption of 8 or more drinks/week significantly reduced the risk of ED (OR=0.85; 99% CI, 0.73-0.99; P=0.007), but consumption of less alcohol (1-7 drinks/week) was not significant (OR=0.73; 99% CI, 0.44, 1.20; P=0.101). Begg's test and Egger's test detected no significant publication bias. Our estimates (in sensitivity analyses) were rendered nonsignificant when International Index of Erectile Function definition was used and when statistical adjustment was made only for age. Meta-analysis of cross-sectional studies yielded a protective association of alcohol on ED, but the two cohort studies did not demonstrate any significant findings for alcohol consumption. More research is needed to confirm whether alcohol is protective or is unrelated to ED development.

Monthly income, standard of living and erectile function in late life.

This was a cross-sectional study that enrolled 160 men aged 50 and above who were sexually active (sexual intercourse in the preceding 6 months) from a large primary care treatment centre. The subjects of interest were elderly aged 65 and above, and men aged 50-65 were used for comparison. The overall response rate was 66.9%. The men who participated were generally more affluent. Standard of living was measured by the presence of maid and housing type. Erectile function (EF) score was significantly higher in those who hired maids (P=0.02). Housing type was not associated with erectile dysfunction (ED). In Model A (included both monthly income and education), significant non-parametric correlations were found between monthly income and EF, intercourse satisfaction (IS), orgasmic function (OF) and sexual desire (SD) domains. After statistical adjustments, only EF (P<0.01) and IS (P=0.04) remained positively associated with monthly income. OF was negatively associated with age (P<0.01) and diabetes (P=0.04), whereas SD was negatively associated with age (P<0.01) in the multivariate analysis. Overall satisfaction was not significantly associated with any factor. In Model B (excluded monthly income from analysis), education attainment was positively associated with OF (P=0.04), but was not significant after adjustment for multiple testing. In the final multivariate model, only monthly income (P<0.01) and age (P<0.01), but not education (P=0.47), remained significantly associated with EF. This study suggests the influence of social determinants on EF and that this influence can extend into late life.

Physical activity and erectile dysfunction: meta-analysis of population-based studies.

We searched for population-based cross-sectional studies, cohort studies and randomized controlled trials (RCTs) on erectile dysfunction (ED) through Medline, PubMed, PsychInfo and scanned though reference lists. Studies that did not include adjusted odds ratios (OR) of physical activity were excluded. Seven cross-sectional studies were suitable for meta-analysis, and the results from one cross-section study, two cohort studies and one RCT were summarized. Pooling the ORs using random effects models, we derived summary estimate for adjusted OR of physical activity in those with ED compared with those without ED, which was 0.53 (0.31, 0.91). Moderate and high physical activities were associated with a lower risk of ED, with ORs at 0.63 (0.43, 0.93) and 0.42 (0.22, 0.82), respectively. Funnel plot by visual inspection, and Begg's test and Egger's test did not detect significant publication bias. Sensitivity analyses revealed that the summary estimate from the random effects model was robust to changes in study sample size and level of statistical adjustment, but not so robust to changes in ED definition, although the summary estimate for each ED definition did not differ significantly. Although causality cannot be demonstrated from cross-sectional studies, the apparent 'protective' effect of physical activity on ED should be further investigated using large-scale cohort studies or RCTs.

Prevalence of erectile dysfunction in Asian populations: a meta-analysis.

We searched for published studies on the prevalence of erectile dysfunction (ED) in Asian populations, through Medline, PubMed, PsychInfo and scanned through reference lists. Data on prevalence rates were obtained and summarized for each Asian region, and were used to calculate pooled prevalence estimates using fixed and random effects models. As significant heterogeneity existed in certain age group categories, the random effects model was preferred. Twenty general population studies were identified. Six studies were eligible to be entered into the pooling of results, and provided 8653 subjects for analysis. The prevalence of ED increased with age. Pooled random effects age-specific prevalence rates were 15.1% (12.2-18.1), 29.6% (19.7-39.6), 40.6% (23.6-57.7), 54.3% (36.0-72.6) and 70.0% (62.3-77.7) for age groups 20-29, 30-39, 40-49, 50-59 and 60-69 years, respectively. Homogeneity of results in age groups 20-29 and 60-69 years suggested equally low and high prevalences of ED across Asian regions in these age groups, respectively. The overall reported prevalence in individual studies ranged from 2 to 81.8%. Prevalence rates and related information were summarized for each Asian region and for each study.

A study of sensitivity of the sustained attention to response task in patients with schizophrenia.

The sustained attention to response task (SART), a measure of sustained attention created by Robertson, Manly, Andrade, Baddeley, and Yiend (1997), was administered to 51 patients with schizophrenia and 51 normal controls to provide information on the sensitivity of the measure in this clinical group. Patients with schizophrenia performed significantly worse than the normal controls in correct response, reaction time for correct response, and efficiency estimate of taking account of both the accuracy and speed of movement. Moreover, the patient group was more often correctly classified as defective on the basis of efficiency estimate than the normal controls. These data provide further evidence of the sensitivity of the SART to patients with schizophrenia.

Problem-solving ability in chronic schizophrenia. A comparison study of patients with traumatic brain injury.

We tested the hypothesis that patients with schizophrenia are more prone to impairment in planning and problem-solving as compared with normal controls and patients with traumatic brain injury (TBI) by administering the Tower of Hanoi (TOH) task. A total of one hundred and fifty-three participants (51 in each group) were recruited. The performance of the patient groups was markedly worse than normal controls in terms of profile score, number of rule-breaking behaviour, and mean execution time. Two-way 3 (group) x 6 (complexity) ANOVAs indicated that significant main effects of group and complexity were observed in the number of moves, planning time to initiate the first move and subsequent execution time. The general performance of TOH in the schizophrenia group was very similar to that of the TBI group. Subsequent comparison of sub-groups of frontal and posterior lobe damage indicated the pattern of performance in schizophrenia patients lie between them. Taken together, these findings suggest that neither focal frontal nor temporal lobe damage is a sufficient explanation for the problem-solving deficits in patients with schizophrenia.