Changes in under-treatment after comprehensive geriatric assessment: an observational study

Under-treatment is frequently present in geriatric patients. Because this patient group often suffer from multiple diseases, polypharmacy (defined as the concomitant chronic use of five or more drugs) and contraindications to indicated drugs may also frequently be present.

To describe the prevalence of under-treatment with respect to frequently indicated medications before and after comprehensive geriatric assessment (CGA) and the prevalence of contraindications to these medications.

The geriatric outpatients evaluated in this study had previously been included in a prospective descriptive study conducted in 2004. Demographic data, medical history, co-morbidity and medication use and changes were documented. The absence of drugs indicated for frequently under-treated conditions before and after CGA was compared. Under-treatment was defined as omission of drug therapy indicated for the treatment or prevention of 13 established diseases or conditions known to be frequently under-treated. Co-morbid conditions were independently classified by two geriatricians, who determined whether or not a condition represented a contraindication to use of these drugs.

In 2004, 807 geriatric outpatients were referred for CGA. Of these, 548 patients had at least one of the 13 selected diseases or conditions. Thirty-two of these patients were excluded from the analysis, leaving 516 patients. Before CGA, 170 of these patients were under-treated (32.9%); after CGA, 115 patients (22.3%) were under-treated. Contraindications were present in 102 of the patients (19.8%) and were more frequent in under-treated patients. After CGA, mean drug use and the prevalence of polypharmacy increased. Although 393 drugs were discontinued after CGA, the overall number of drugs used increased from 3177 before CGA to 3424 after CGA. Five times more drugs were initiated for a new diagnosis than for correction of under-treatment.

Under-treatment is significantly reduced after CGA. Patients with contraindications to indicated medicines are more frequently under-treated. CGA leads to an increase in polypharmacy, mainly because of new conditions being diagnosed and despite frequent discontinuation of medications.