The stress associated with providing unpaid care for a sick or disabled adult is leading to a 29% greater use of anti-anxiety medicines among such caregivers, compared those who do not provide such care, a US study has found.

Use of medications to treat conditions for which stress is the common denominator - including high blood pressure, depression, anxiety and ulcers - is higher among caregivers, with the widest difference seen in the use of medicines to treat anxiety, according to the research, from pharmacy benefit manager (PBM) Express Scripts.

"An estimated 42 million Americans serve as a caregiver to a relative or friend, and that number will grow significantly as the boomer population ages," according to Bob Nease, chief scientist at Express Scripts. The firm’s research finds that 63% of caregivers in the US are female and 37% are male, and that their average age is 52.

The study also reveals that:

- while antidepressants must be taken as prescribed in order to provide a benefit, adherence rates for caregivers who use such medicines are relatively worse than for non-caregivers, at 67% versus 73%, respectively. And across all health conditions, 64% of caregivers are adherent to their medication therapy, compared to 68% of non-caregivers;

- caregivers are more likely to rate themselves in poorer health compared to non-caregivers (15% vs 12%) and as being unhappy (5.3% vs 3.5%);

- only one in five caregivers reside in the same household as the patients in their care, with 52% living within 15 miles of their primary care recipient and another 27% living more than 15 miles away; and

- approximately one-third of all caregivers in the US provide for more than one person, while two-thirds are providing care for a patient, older relative, sibling or friend, as opposed to a spouse or adult child.

And at the time of the survey, approximately 36% of caregivers had increased the amount of care they provided in the past month, while for 15% this had decreased. 

"The good news for caregivers is the ever-increasing availability of tools - auto-refills for prescriptions, longer-day supplies of medication, mobile apps and websites that offer alerts, prescription histories and adherence reminders - that can help them stay on track with their own health decisions, while also reducing the administrative burden that comes with being a caregiver," said Dr Nease.