Publications of the Week, January 2

Below are the articles selected as suggested reading for this week by editors from McMaster University.

Religious service attendance and mortality among women

Attending religious services was associated with lower mortality.

This publication examined the association between attending religious services and subsequent mortality among women participating in the Nurses’ Health Study. It used a self-reported questionnaire to examine >70,000 women who were free of cardiovascular disease and cancer at baseline and followed them for about 16 years.

The analysis was adjusted for baseline risk-factors (such as age, diabetes mellitus, hypertension) and major lifestyle factors, including smoking, physical function, education, and social integration (marital status, number of friends and relatives, attendance at religious services at baseline). Subsequent attendance at religious services more than once per week in comparison with not attending at all was associated with the total mortality lower by about a third (hazard ratio [HR], 0.67; 95% confidence interval [CI], 0.62-0.71), including lower cardiovascular mortality (HR, 0.73) and cancer mortality (HR, 0.79). In comparison with those not attending religious services, the mortality was also lower among those attending once a week (HR, 0.74) and less than once per week (HR, 0.87).

The authors examined a number of pathways potentially mediating between attending religious services and subsequent mortality by not only exploring risk factors at baseline but also by exploring their changes with time. They found that a substantial part of this association (about two-thirds) could be explained – after controlling for baseline factors – by less smoking, more social interaction, less depression, and more optimism.

*Editors thank the corresponding author of the original study, Dr. VanderWeele, for providing additional information.

α-Blockers and ureteric stones

Confirmation by meta-analysis: promoting passage of kidney stones using α-blockers is beneficial.

This publication examined the effects of α-blockers (mostly tamsulosin, used in >40 original studies, but a few studies examined also the effects of alfuzosin, doxazosin, silodosin, terazosin, and naftopidil) on the passage of ureteric stones. The authors conducted this meta-analysis after a recent large trial raised questions regarding this management strategy.

The probability of stone passage was increased by about half with α-blocker treatment (pooled benefit ratio of 1.49, 95% confidence interval of 1.39-1.61). Mean time to stone passage in the intervention versus control group was 8.8 and 13.3 days, and the pooled probability for stone passage was about 76% versus about 48%, respectively. The benefit was not present for smaller stones (<5 mm), and relative benefit was increased by about 10% for every 1 mm increase in stone size; it was irrespective of stone location (upper or middle vs lower ureteric stone) and there was no evidence of a specific α-blocker effect. The effect was more easily noticeable in studies with a smaller chance of spontaneous stone passage, which according to authors may explain the recent negative result of a large study leading to this meta-analysis.

Long-term oxygen in patients with COPD and moderate desaturation

Use of supplemental oxygen has no beneficial effect in patients with stable chronic obstructive pulmonary disease (COPD) and moderate desaturation at rest or at exertion. This study included COPD patients with moderate resting desaturation (89%-93%) and moderate exercise-induced desaturation (during the 6-minute walk test, <90% saturation for at least 10 seconds but ≥80% for at least 5 minutes). Supplemental oxygen was used 24 hours per day in those with resting desaturation and during sleep and exercise among those with exercise-induced hypoxia.

Over 700 patients were followed for 1 to 6 years (median, 18 months). Most patients in the active treatment group used 2 L of oxygen per minute. Use of oxygen in this population had no clear beneficial effects in comparison to no oxygen use on all examined outcomes: time to death or first hospitalization, rate of death (rate per 100 person-years in the group with and without supplemental oxygen, 5.2% vs 5.7%), rates of first hospitalization for any cause (rate per 100 person-years, 31.6% vs 34.5%), rates of COPD exacerbations, quality of life, lung function, and walking distance.