Pain management in the elderly population: a review.

The elderly population comprises the fastest growing segment of the world's population. As patients age, the incidence and prevalence of certain pain syndromes increase. Pain may be underreported as some elderly patients incorrectly believe that pain is a normal process of aging. A comprehensive pain assessment includes a thorough medical history and physical examination, review of systems and pertinent laboratory results, imaging studies, and diagnostic tests. Pain physicians should have a broad range of understanding of the pharmacologic and physiological changes that occur in the geriatric population. The present review on pain management in the elderly focuses on relevant information for the pain clinician. Included are appropriate pain assessment, physical examination, pathophysiologic changes in the elderly, pharmacokinetic and pharmacodynamic changes, and present pain management modalities. Elderly patients present with increased fat mass, decreased muscle mass, and decreased body water, all of which have important ramifications on drug distribution. Hepatic phase I reactions involving oxidation, hydrolysis, and reduction appear to be more altered by age than phase II conjugation such as acetylation, glucuronidation, sulfation, and glycine conjugation. There is a predictable age-related decline in cytochrome P-450 function and, combined with the polypharmacy that much of the elderly population experiences, this may lead to a toxic reaction of medications. One of the newer opiates, oxymorphone, has recently been studied as it is metabolized in a non-cytochrome P-450 pathway and therefore bypasses many of the drug-drug interactions common to the elderly. A multidisciplinary approach is recommended to investigate all possible options for optimal management, including pharmacotherapy, interventional procedures, physical rehabilitation, and psychological support.