Cost-effectiveness Assessment of Cardiac Interventions: Determining a Socially Acceptable Cost Threshold.

Health care is a vital good for which there is an infinite demand. However, societal resources are finite and need to be distributed efficiently to avoid waste. Thus, the relative value of an intervention - cost compared to its effectiveness- needs to be taken into consideration when deciding which interventions to adopt. Cost-effectiveness analysis provides the crucial information which guides these decisions. As the field of medicine and indeed cardiology move forward with innovations which are effective but often expensive, it becomes imperative to employ these cost-effectiveness analytic tools, not with the intention of denying vital health services but to ascertain what the society willing to pay for.

Nocturnal heart rate variability is lower in temporomandibular disorder patients than in healthy, pain-free individuals.

AIMS: To determine whether patients with a painful myofascial temporomandibular disorder (TMD) have diminished nocturnal heart rate variability (HRV), a marker of autonomic nervous system (ANS) dysfunction, relative to healthy, pain-free controls. METHODS: Participants with myofascial TMD and healthy, pain-free volunteers underwent nocturnal polysomnography studies during which HRV indices were measured. Multiple linear regression analyses were used to determine whether TMD status exerted unique effects on HRV. RESULTS: Ninety-five participants (n = 37 TMD; n = 58 controls) were included in the analyses. The TMD group had a lower standard deviation of R-R intervals (89.81 ± 23.54 ms versus 107.93 ± 34.42 ms, P ⋜ .01), a lower root mean squared successive difference (RMSSD) of R-R intervals (54.78 ± 27.37 ms versus 81.88 ± 46.43 ms, P < .01), and a lower high frequency spectral power (2336.89 ± 1224.64 ms² versus 2861.78 ± 1319 ms², P = .05) than the control group. The ratio of the low-frequency (LF) to the high-frequency (HF) spectral power was higher in the TMD group (2.47 ± 2 versus 1.38 ± 0.65, P < .01). The differences in RMSSD (91.21 ms versus 112.03 ms, P = .05) and LF:HF ratio (0.71 versus 0.32, P < .01) remained significant after controlling for age and psychological distress. CONCLUSION: Myofascial TMD patients revealed lower nocturnal HRV than healthy, pain-free controls. Further research should focus on processes that address this ANS imbalance, which may potentially lead to effective therapeutic interventions.

Depressive symptoms, physical inactivity and risk of cardiovascular mortality in older adults: the Cardiovascular Health Study.

BACKGROUND: Depressed older individuals have a higher mortality than older persons without depression. Depression is associated with physical inactivity, and low levels of physical activity have been shown in some cohorts to be a partial mediator of the relationship between depression and cardiovascular events and mortality. METHODS: A cohort of 5888 individuals (mean 72.8 ± 5.6 years, 58% female, 16% African-American) from four US communities was followed for an average of 10.3 years. Self-reported depressive symptoms (10-item Center for Epidemiological Studies Depression Scale) were assessed annually and self-reported physical activity was assessed at baseline and at 3 and 7 years. To estimate how much of the increased risk of cardiovascular mortality associated with depressive symptoms was due to physical inactivity, Cox regression with time-varying covariates was used to determine the percentage change in the log HR of depressive symptoms for cardiovascular mortality after adding physical activity variables. RESULTS: At baseline, 20% of participants scored above the cut-off for depressive symptoms. There were 2915 deaths (49.8%), of which 1176 (20.1%) were from cardiovascular causes. Depressive symptoms and physical inactivity each independently increased the risk of cardiovascular mortality and were strongly associated with each other (all p < 0.001). Individuals with both depressive symptoms and physical inactivity had greater cardiovascular mortality than those with either individually (p < 0.001, log rank test). Physical inactivity reduced the log HR of depressive symptoms for cardiovascular mortality by 26% after adjustment. This was similar for persons with (25%) and without (23%) established coronary heart disease. CONCLUSIONS: Physical inactivity accounted for a significant proportion of the risk of cardiovascular mortality due to depressive symptoms in older adults, regardless of coronary heart disease status.

The association of depression with adherence to antihypertensive medications: a systematic review.

OBJECTIVE: To examine the strength and consistency of the evidence on the relationship between depression and adherence to antihypertensive medications. METHODS: The MEDLINE, CINAHL, PsycINFO, Embase, SCOPUS, and ISI databases were searched from inception until 11 December 2009 for published studies of original research that assessed adherence to antihypertensive medications and used a standardized interview, validated questionnaire, or International Classification of Diseases Ninth Revision code to assess depression or symptoms of depression in patients with hypertension. Manual searching was conducted on 22 selected journals. Citations of included articles were tracked using Web of Science and Google Scholar. Two investigators independently extracted data from the selected articles and discrepancies were resolved by consensus. RESULTS: Eight studies were identified that included a total of 42,790 patients. Ninety-five percent of these patients were from one study. Only four of the studies had the assessment of this relationship as a primary objective. Adherence rates varied from 29 to 91%. There were widely varying results within and across studies. All eight studies reported at least one significant bivariate or multivariate negative relationship between depression and adherence to antihypertensive medications. Insignificant findings in bivariate or multivariate analyses were reported in six of eight studies. CONCLUSION: All studies reported statistically significant relationships between depression and poor adherence to antihypertensive medications, but definitive conclusions cannot be drawn because of substantial heterogeneity between studies with respect to the assessment of depression and adherence, as well as inconsistencies in results both within and between studies. Additional studies would help clarify this relationship.