Alcohol and drug use disorders in patients with cancer and caregivers: effects on caregiver burden

Alcohol and drug use disorders can negatively impact on the quality of life of people living with cancer and their caregivers. Despite 8% of cancer deaths in men, and 3% in women, attributable to excessive alcohol consumption, the extent of continued problems with alcohol and drug use is unknown.

Alcohol and drug use disorders can also be associated with high levels of distress and low levels of well-being in carers of people with long term conditions. It is unclear whether there is a relationship between carer burden and alcohol and drug use disorders specifically in cancer patients. It is important to identify any relationships between patient and caregiver problems and alcohol and drug use disorders to be able to provide appropriate intervention and support for those who are struggling.

The aim of this study, supported by Alcohol Change UK, was to establish the prevalence of alcohol and drug use disorders in a large cohort of advanced cancer patients and their caregivers. Secondary aims were to evaluate the relationship between these problems and patient physical and psychological symptoms and carer burden. An overarching purpose of the study is to establish a large accurate dataset to determine if screening would be required for certain cohorts.

The cancer patient and caregiver completed the Alcohol Use Disorders Identification Tool (AUDIT), CAGE questionnaire (alcohol dependence), and Drug Abuse Screening Test. The patient completed the Memorial Symptom Assessment Scale- Short Form (symptom assessment tool), and caregiver completed the Zarit Burden Questionnaire (carer burden assessment tool).

The aim of the study was to recruit 500 cancer patients and respective caregivers. Statistical analysis compared cases and non-cases of alcohol and drug use disorders with symptom and burden score.

1. Five-hundred and seven cancer patients and their respective caregivers were recruited.
2. Twenty-seven patients (5%) and forty-four caregivers (8%) screened positively for alcohol use disorders on the AUDIT. In eight cases both the patient and caregiver screened positively.
3. Fifty-seven patients (11%) and forty-eight caregivers (9%) screened positively for lifetime alcohol dependence using the CAGE questionnaire.
4. Eighty five percent (85%) of patients, and twenty seven percent (27%) of carers, were taking regular painkillers. The majority of painkillers were prescribed opioids. Thirty patients (6%), and sixteen caregivers (3%), screened positively for drug abuse problems on the DAST-10.
5. There was a significantly higher caregiver burden score in caregivers screening positively for alcohol and drug abuse problems on the AUDIT, CAGE and DAST-10.
6. Patients with AUDIT defined alcohol problems had lower global distress index (MSAS-GDI) and physical symptom scores (MSAS-PHYS) than those without. There was no difference in psychological symptoms (MSAS-PSYCH) between groups.
7. Caregiver burden was not affected by the patient’s drug or alcohol abuse issues.
8. There was no difference in physical or psychological symptoms between patients screening positively and negatively with the CAGE or DAST-10.

The association of alcohol and drug use disorders with caregiver burden indicates the importance of screening and supporting this group. An individualised needs assessment is recommended to identify issues and implement support strategies. All patients started on strong painkillers should be monitored for drug misuse especially as many are now living with cancer, and taking painkillers, for longer time periods.

The prevalence of cancer patients’ alcohol use disorders and dependence was lower than reported in previous studies. Only 5% of patients had harmful levels of alcohol use disorders in the previous year (AUDIT positive) with a higher number having a positive CAGE (11%). The CAGE questionnaire assessed lifetime dependence rather than current issues suggesting a proportion of patients had previously had problems but weren’t currently using alcohol harmfully.

The level of current alcohol use disorders in patients and caregivers is lower than the general population for this age range taking into account sex differences. However, lifetime alcohol dependence rates (CAGE) are higher than equivalent general population for both patients and caregivers. This suggests that individuals with previous issues do not necessarily have current patterns of misuse but must be evaluated carefully and non-judgmentally.

Eighty-five percent of patients were taking prescribed painkillers and six percent screened positively for drug abuse. This is the first estimated prevalence rate of drug abuse in cancer patients in the United Kingdom and is higher than general population levels accounting for age (aged 55+ drug abuse rates are less than 1%). Twenty-seven percent of caregivers were taking prescribed painkillers. This is higher than United Kingdom general population data and indicates that caregivers have significant health care needs and morbidity of their own.