NEW ORLEANS – Elderly dementia patients who take antipsychotics are significantly less likely to have guideline-concordant metabolic checkups than are patients without dementia who take the drugs.
There seems to be no universal reason why this should be so, but the findings of a large retrospective study do suggest that providers should be aware of the problem and make an effort to improve follow-up monitoring, Dr. Dinesh Mittal said at the annual meeting of the American Association for Geriatric Psychiatry.
Dr. Dinesh Mittal
“Metabolic side effects possibly contribute to mortality in elderly patients,” said Dr. Mittal of the Central Arkansas Veterans Healthcare System, North Little Rock. “Because of this, it’s important to monitor outpatients with dementia receiving antipsychotics, especially because the drugs do not have demonstrated efficacy in managing behavioral symptoms of dementia.”
He presented a retrospective cohort analysis of 1,576 matched pairs of elderly Veterans Affairs patients with an index prescription for an antipsychotic. Half of the group had dementia but not psychosis, and the other half had a psychosis but not dementia.
The primary outcomes were metabolic monitoring at both baseline and the 3-month follow-up visit. Metabolic measures considered were weight, glucose or hemoglobin A1c, and low-density lipoprotein (LDL) cholesterol.
Because the patients with dementia were significantly older and differed on most demographic and clinical variables than those without dementia, the authors used propensity matching to even the groups. Their mean age in the matched sample was 73 years. A quarter had diabetes at baseline. Half had dyslipidemia and half hypertension, 30% were obese, and 15% had some form of heart disease.
About 10% were taking a medication with a high risk of metabolic derangement (clozapine, olanzapine). Most (70%) were taking a drug with a moderate risk (risperidone, chlorpromazine, paliperidone, thiothixene, or trifluoperazine). A low-risk drug was prescribed to the rest of the patients (aripiprazole, ziprasidone, haloperidol, fluphenazine, molindone, pimozide, or mesoridazine).
Even at baseline, the frequency of metabolic measurements was suboptimal, Dr. Mittal said. Weight most often was recorded (68% of dementia patents vs. 64% for the psychosis patients). Less than half of each group had a glucose measurement obtained (41% in the dementia group vs. 44% in the psychosis group). LDL cholesterol was obtained in just a quarter (24% vs. 27%, respectively).
Compared with baseline, significantly fewer patients in each group had 3-month measurements; there also were significant between-group differences, with dementia patients getting less attention. Weight was obtained in 46% of the group with dementia and 51% of the psychosis group, glucose in 26% of the dementia group and 31% of the psychosis group, and LDL in 13% of the dementia group and 18% of the psychosis group.
“We were quite surprised at the findings, as we had expected the rates to be much higher given the [Food and Drug Administration] warnings about the risk of metabolic derangement and mortality with antipsychotic medications,” Dr. Mittal noted.
Reasons for the poor monitoring, especially in dementia patients, are unclear, he said.
“One possible reason may be that monitoring recommendations were developed to apply to any patient treated with a second-generation antipsychotic but did not specifically mention monitoring for patients with dementia. The perception among providers may be that these guidelines apply to patients with psychosis only,” he suggested.
It’s unlikely that transportation problems for patients cared for at home, or lack of understanding about the need for tests, are the cause. An exploratory analysis concluded that 95% of the dementia patients had at least one baseline visit and 75% had at least one follow-up visit during the 3 months after medication initiation.
Some clinicians could view medication-related weight gain as helpful for dementia patients, who tend to lose weight as the disease progresses, but “our sample included only patients with dementia who were being managed in the outpatient setting and were thus likely to have less advanced dementia than those in nursing homes who are more likely to have lost significant weight to warrant such a drastic intervention,” Dr. Mittal said.
The findings are in sharp contrast to the existing guidelines, he pointed out.
In 2004, the American Diabetes Association, American Psychiatric Association, American Association of Clinical Endocrinologists, and North American Association for the Study of Obesity published a consensus statement on the issue. It recommended assessing metabolic parameters at baseline and at 4, 8, and 12 weeks after treatment initiation. Monitoring also should be conducted quarterly, annually, and every 5 years, the statement noted.
A 2012 literature review upheld this recommendation, suggesting that patients with a history of cardiac disease receive extra attention.