Health benefit costs and absenteeism due to insomnia from the employer's perspective: a retrospective, case-control,...

To objectively assess the economic impact of insomnia on direct medical and prescription costs and indirect absence-related salary replacement costs and on absences and to compare the prevalence and costs of comorbidities in employees with and without insomnia.

A retrospective analysis was performed on employee data from the Human Capital Management Services Research Reference Database (January 2001-September 2007). Employees were identified as having insomnia (ICD-9 criteria) based on history of receiving medications used to treat insomnia or physician's diagnosis of insomnia. Control employees had no history of medications used to treat insomnia and no insomnia diagnosis. Annual costs and number of absences were compared using 2-part regression models, controlling for demographics, job information, geographic region, comorbid disorders, and the Charlson Comorbidity Index score. Comorbidity prevalence, costs, and services were compared.

Data were collected for 299,188 employees (17,230 employees with insomnia and 281,958 control employees). Annual mean incremental costs were $2,053 greater (in total) for employees with insomnia compared with controls (specific increments: medical $751, drug $735, sick leave $208, short-term disability $179, long-term disability $10, and workers' compensation $170). Employees with insomnia missed a mean of 3.10 more workdays annually than those without insomnia. Nearly all comorbid conditions were more prevalent, were more costly, and resulted in a greater utilization of services in employees with insomnia compared to those without. All of the above comparisons were significant (P < .05).

Insomnia was associated with increased costs, greater absenteeism, and an increased number of comorbid conditions in an employed population. Consistent with other analyses based on these data, the study estimated the annual cost of insomnia in the US civilian labor force to be approximately $15.0-17.7 billion (US dollars).