INTRODUCTION

Nocturia, a common symptom, is defined as waking at night to void, where each micturition is preceded and followed by sleep [1]. Although by definition even a single episode of awakening to urinate is nocturia, epidemiological evidence and expert clinical opinion both suggest nocturia is likely clinically meaningful if a patient voids two or more times nightly [2]. Patients themselves are more likely to consult a provider about nocturia if they have three or more episodes [3]. Nocturnal urinary incontinence or nighttime bed-wetting (enuresis) is distinct from nocturia.

Nocturia is a source of significant bother for some patients [4]. Nocturia is one of the most distressing symptoms in older men with benign prostatic hyperplasia (BPH) [5] and is the lower urinary tract symptom most strongly associated with poor quality of life ratings [6]. Patients report nocturia as a leading cause of sleep disturbance, affecting both sleep onset and maintenance [7]. Nocturia is associated with increased rates of depression [8], work absenteeism [9], lower self-rated physical and mental health [10], congestive heart failure [11], and increased all cause mortality [12]. In the very old, nocturia is associated with higher rates of accidental falls [13,14] and fractures [15,16].

Because nocturia is associated with a variety of clinical syndromes and disorders [17], the diagnostic approach is often challenging, and treatment may result in only small improvement [18].

This topic will discuss the clinical presentation, diagnosis, and treatment of nocturia in adults. Detailed discussions of some conditions that cause or are associated with nocturia are presented separately. (See "Diagnosis of polyuria and diabetes insipidus" and "Clinical manifestations and diagnostic evaluation of benign prostatic hyperplasia" and "Clinical presentation and diagnosis of urinary incontinence".)

EPIDEMIOLOGY

The prevalence of nocturia is higher with increasing age [10,19-21]. Occasional nocturia is present in 50 percent of men and women aged 50 to 59 years. Among 18 to 49 year olds, more women than men have nocturia; the sex ratio reverses after 60 years of age, with prevalence greater in men than women [19]. The prevalence of twice nightly or greater nocturia among men between 70 and 79 is nearly 50 percent [19].