Suboccipital decompression enhances heart rate variability indices of cardiac control in healthy subjects.

OBJECTIVES: Osteopathic manipulative treatment (OMT) focused on the upper cervical spine is theorized to affect the function of the vagus nerve and thereby influence the parasympathetic branch of the autonomic nervous system. This study was designed to determine the acute effect of upper cervical spine manipulation on cardiac autonomic control as measured by heart rate variability. DESIGN: Nineteen healthy, young adult subjects underwent three different experimental interventions administered in random order: cervical OMT, sham manipulation, and time control. Six minutes of electrocardiographic data were collected before and after each intervention, and heart rate variability was assessed by both time-domain and frequency-domain measures. RESULTS: No differences in resting heart rate or any measure of heart rate variability were observed between the baseline periods prior to each intervention. The OMT protocol resulted in an increase in the standard deviation of the normal-to-normal intervals (0.12±0.082 seconds, p<0.01), an increase in the high frequency spectral power (p=0.03), and a decrease in the low/high frequency spectral ratio (p=0.01) relative to the sham and time control conditions. No significant differences between sham and time control were observed (p>0.11 for all variables). CONCLUSIONS: These data support the hypothesis that upper cervical spine manipulation can acutely affect measures of heart rate variability in healthy individuals.

Controlling lipids in a high-risk population with documented coronary artery disease for secondary prevention: are we doing enough?

BACKGROUND: The prevalence of high-density lipoprotein cholesterol (HDL-C) in patients who have achieved low-density lipoprotein cholesterol (LDL-C) targets in the current era of universal statin therapy remains unknown. We conducted a study to determine the prevalence of low HDL-C in patients with documented coronary artery disease, and to determine the lipid-lowering treatment patterns in secondary prevention of coronary artery disease. METHODS: In this retrospective cohort analysis, data were obtained from the electronic database of a cardiology clinic. The Joint British Society 2 criteria were used defining low HDL-C as less than 1 mmol/l in males and less than 1.2 mmol/l in females. We compared the prevalence of low HDL-C across the following categories of LDL-C: less than 2, 2-2.5, and greater than 2.5 mmol/l. RESULTS: Two thousand and eighty-seven patients with a mean age of 64.34±11.94 years constituted the study sample. About 36.6% of patients in this study were found to have low HDL-C. Irrespective of sex, low HDL-C was prevalent across all levels of LDL-C, but interestingly this was most prevalent in patients with a LDL-C less than 2 mmol/l (43.06%). HDL-C level of 1.16±0.97 mmol/l in patients with LDL-C less than 2 mmol/l was significantly lower than 1.22±0.33 mmol/l in patients with LDL-C greater than 2 mmol/l, P value less than 0.01. There was a poor correlation between levels of HDL-C and LDL-C in the study population irrespective of sex or statin therapy. CONCLUSION: This study shows widely prevalent low HDL-C levels in high-risk patients across the spectrum of LDL-C levels despite statin therapy. There was no correlation between the LDL-C and HDL-C levels implying their independent relationship and, thus, the need to treat them independently.