Effect of pravastatin on human sleep

The impact of glucocorticoids and statins on sleep quality

Glucocorticoids and statins are the foundation of lifelong therapies and as such, may generate a variety of side effects. Among these, sleep impairments are one of the least explored and, simultaneously, majorly underestimated in clinical practice. Based on the available evidence, we have concluded that glucocorticoid action on the suprachiasmatic nucleus (SCN) that drives sleep disturbances is dual in nature. It involves both serotonin depletion and reduced arginine vasopressin signalling in the SCN. The former seems to involve activation of glucocorticoid receptors in the dorsal raphe, whereas the latter likely results from changes in glucose serum levels affecting the SCN, among other blood-borne factors which are yet to be discovered. Literature remains inconclusive when it comes to statins. Their diverse potential to cross the blood-brain barrier is considered the key factor determining statins' capability to evoke sleep impairments. Concurrently, an effect similar to that produced by steroids occurs - alteration in serum levels of blood-borne factors, such as glucose, which is a likely cause of statin-induced sleep disturbances.

Sleep changes following statin therapy: a systematic review and meta-analysis of randomized placebo-controlled polysomnographic trials

INTRODUCTION

Statin use might be associated with an increased risk of sleep disturbances including insomnia, but the evidence regarding sleep changes following statin therapy has not been conclusive. Therefore we assessed the impact of statin therapy on sleep changes through a systematic review and meta-analysis of available randomized controlled trials (RCTs).

MATERIAL AND METHODS

We searched MEDLINE and SCOPUS up to October 1, 2014 to identify placebo-controlled RCTs investigating the effect of statin therapy on sleep changes. A meta-analysis was performed using either a fixed-effects or a random-effect model according to the I2 statistic. Effect size was expressed as weighted mean difference (WMD) and 95% confidence interval (CI).

RESULTS

Overall, the impact of statin therapy on polysomnography (PSG) indices of sleep was reported in 5 trials comprising 9 treatment arms. Overall, statin therapy had no significant effect on total sleep duration (WMD: -7.75 min, 95% CI: -18.98, 3.48, p = 0.176), sleep efficiency (WMD: 0.09%, 95% CI: -2.27, 2.46, p = 0.940), entries to stage I (WMD: 0.36, 95% CI: -0.91, 1.63, p = 0.580), or latency to stage I (WMD: -1.92 min, 95% CI: -4.74, 0.89, p = 0.181). In contrast, statin therapy significantly reduced wake time (WMD: -4.43 min, 95% CI: -7.77, -0.88, p = 0.014) and number of awakenings (WMD: -0.40, 95% CI: -0.46, -0.33, p < 0.001). Meta-regression did not suggest any correlation between changes in wake time and awakening episodes with duration of treatment and LDL-lowering effect of statins.

CONCLUSIONS

The results indicated that statins have no significant adverse effect on sleep duration and efficiency, entry to stage I, or latency to stage I sleep, but significantly reduce wake time and number of awakenings.

Conceptual foundations of the UCSD Statin Study: a randomized controlled trial assessing the impact of statins on cognition, behavior, and biochemistry

BACKGROUND

Statin cholesterol-lowering drugs are among the most prescribed drugs in the United States. Their cardiac benefits are substantial and well supported. However, there has been persistent controversy regarding possible favorable or adverse effects of statins or of cholesterol reduction on cognition, mood, and behavior (including aggressive or violent behavior).

METHODS

The literature pertaining to the relationship of cholesterol or statins to several noncardiac domains was reviewed, including the link between statins (or cholesterol) and cognition, aggression, and serotonin.

RESULTS

There are reasons to think both favorable and adverse effects of statins and low cholesterol on cognition may pertain; the balance of these factors requires further elucidation. A substantial body of literature links low cholesterol level to aggressive behavior; statin randomized trials have not supported a connection, but they have not been designed to address this issue. A limited number of reports suggest a connection between reduced cholesterol level and reduced serotonin level, but more information is needed with serotonin measures that are practical for clinical use. Whether lipophilic and hydrophilic statins differ in their impact should be assessed.

CONCLUSION

There is a strong need for randomized controlled trial data to more clearly establish the impact of hydrophilic and lipophilic statins on cognition, aggression, and serotonin, as well as on other measures relevant to risks and quality-of-life impact in noncardiac domains.

Pravastatin. A reappraisal of its pharmacological properties and clinical effectiveness in the management of coronary heart disease

Pravastatin is an HMG-CoA reductase inhibitor which lowers plasma cholesterol levels by inhibiting de novo cholesterol synthesis. Pravastatin produces consistent dose-dependent reductions in both total and low density lipoprotein (LDL)-cholesterol levels in patients with primary hypercholesterolaemia. Favourable changes in other parameters such as total triglyceride and high density lipoprotein (HDL)-cholesterol levels are generally modest. Combination therapy with other antihyperlipidaemic agents such as cholestyramine further enhances the efficacy of pravastatin in patients with severe dyslipidaemias. Available data suggest that pravastatin is effective in elderly patients and in patients with hypercholesterolaemia secondary to diabetes mellitus or renal disease. The benefit of cholesterol-lowering in terms of patient outcomes is currently an area of considerable interest. Recently completed regression studies (PLAC I, PLAC II, KAPS and REGRESS) show that pravastatin slows progression of atherosclerosis and lowers the incidence of coronary events in patients with mild to moderately severe hypercholesterolaemia and known coronary heart disease. Large scale primary (WOSCOPS) and secondary (CARE) prevention studies, moreover, demonstrate that pravastatin has beneficial effects on coronary morbidity and mortality. In WOSCOPS, all-cause mortality was reduced by 22%. Pravastatin is generally well tolerated by most patients (including the elderly), as evidenced by data from studies of up to 5 years in duration. As with other HMG-CoA reductase inhibitors, myopathy occurs rarely (< 0.1% of patients treated with pravastatin): approximately 1 to 2% of patients may present with raised serum levels of hepatic transaminases. Thus, with its favourable effects on cardiovascular morbidity/mortality and total mortality, pravastatin should be considered a first-line agent in patients with elevated cholesterol levels, multiple risk factors or coronary heart disease who are at high risk of cardiovascular morbidity.