OBJECTIVES: Insomnia - defined as a difficulty in initiating or maintaining sleep – is known to accompany chronic diseases as comorbidity. Nevertheless, the impact of insomnia - as a comorbidity of overactive bladder and incontinence-  on overall burden of illness is unclear. The objective of our study was thus to analyze the impact of insomnia as comorbidity of urological diseases on burden of illness of over a five year period. METHODS: In 2007, two representative adult samples of the Kantar Health European Healthcare Panel in Germany and UK were surveyed (n=72.605) and self-reports about insomnia, overactive bladder and incontinence were collected. In 2012, a subsample of 4.008 individuals was re-contacted and participants completed a general health, functional status and work disability questionnaire. RESULTS: In 2007, 3.2% of the initial representative sample reported overactive bladder, and 6.9% incontinence. A total of 38.9% of the individuals with one or both of these problems also suffered from insomnia. Five years later, in 2012, 26.1% of the entire group of individuals with one or both of the urological diseases indicated very good or excellent health, 45.9% experienced functional limitations and 28.1% suffered from work disability. In the subgroup of individuals with urological diseases in combination with insomnia, the percentage of individuals with very good/excellent health dropped to 15.2%, functional limitations increased to 61%, and 41.7% persons were disabled at their workplace. CONCLUSIONS: As these results demonstrate, insomnia is an important comorbidity of urological diseases and intensifies related burden of illness and reduces work related performance. Insomnia should be considered for inclusion into appropriate treatment strategies for urological diseases.