Health care utilisation following childhood acute lymphoblastic leukaemia: a population-based matched cohort study

Long-term diagnosis-specific sickness absence, disability pension, and healthcare use in 1305 young adult childhood cancer survivors and in 6430 references; a Swedish ten-year prospective cohort study

Background

Childhood cancer survivors (CCS) are at high risk of chronic health conditions. We aimed to explore young adult CCS’ and matched references’ future diagnoses-specific healthcare use, sickness absence (SA), and disability pension (DP).

Methods

We performed a prospective cohort study with microdata from seven nationwide Swedish registers. We included 1305 young adult CCS born 1983–1988 and living in Sweden in 2008 and 6430 matched references and followed them for ten years (2009–2018) regarding mean annual specialized outpatient visits, inpatient days, and SA (spells >14 days) and/or DP (SADP) days, overall and by eight diagnostic groups. Risk factors for >90 SADP days in 2018 were explored as odds ratios (OR) with 95% confidence intervals (CI) by adjusted logistic regression.

Results

Approximately 80% of CCS and 90% of references did not have SADP in the ten-year follow-up. Mean SADP days/year was higher among CCS (40–50 days/year), particularly in CNS tumor survivors (76–83 days/year), compared to references (12–18 days/year). Most SADP days were DP days. CCS had more mean outpatient visits (1.6–1.8 visits/year) and inpatient days (0.8–1.7 days/year) than references (0.8–1.2 visits/year and 0.6–0.75 days/year, respectively). The main healthcare use and SADP diagnoses were neoplasms and psychiatric disorders among all CCS, along with nervous system and endocrine conditions among CNS tumor survivors. The risk of SADP >90 days in 2018 was higher among female compared to male CCS (OR = 2.34, 95% CI 1.67–3.32), those with elementary schooling compared to high school/university education (OR = 6.52, 95% CI 4.49–9.49), and survivors of CNS tumors compared to other malignancies (OR hematological versus CNS = 2.88, 95% CI 1.95–4.28; OR hematological versus non-CNS solid tumors = 0.71, 95% CI 0.45–1.09).

Conclusions

Most CCS did not have SADP as young adults; nevertheless, their risk of SADP was higher than among matched references. CNS tumor survivors were at particularly high risk of SADP.

Excess morbidity and mortality among survivors of childhood acute lymphoblastic leukaemia: 25 years of follow-up from the United Kingdom Childhood Cancer Study (UKCCS) population-based matched cohort

OBJECTIVES

To examine morbidity and mortality among teenagers and young adults (TYAs) previously diagnosed with acute lymphoblastic leukaemia (ALL) in childhood, and compare to the general TYA population.

DESIGN

National population-based sex-matched and age-matched case-control study converted into a matched cohort, with follow-up linkage to administrative healthcare databases.

SETTING

The study population comprised all children (0-14 years) registered for primary care with the National Health Service (NHS) in England 1992-1996.

PARTICIPANTS

1082 5-year survivors of ALL diagnosed<15 years of age (1992-1996) and 2018 unaffected individuals; followed up to 15 March 2020.

MAIN OUTCOME MEASURES

Associations with hospital activity, cancer and mortality were assessed using incidence rate ratios (IRR) and differences.

RESULTS

Mortality in the 5-year ALL survivor cohort was 20 times higher than in the comparison cohort (rate ratio 21.3, 95% CI 11.2 to 45.6), and cancer incidence 10 times higher (IRR 9.9 95% CI 4.1 to 29.1). Hospital activity was increased for many clinical specialties, the strongest associations being for endocrinology; outpatient IRR 36.7, 95% CI 17.3 to 93.4 and inpatient 19.7, 95% CI 7.9 to 63.2 for males, and 11.0, 95% CI 6.2 to 21.1 and 6.2 95% CI 3.1 to 13.5, respectively, for females. Notable excesses were also evident for cardiology, neurology, ophthalmology, respiratory medicine and general medicine. Males were also more likely to attend gastroenterology; ear, nose and throat; urology; and dermatology, while females were more likely to be seen in plastic surgery and less likely in midwifery.

CONCLUSIONS

Adding to excess risks of death and cancer, survivors of childhood ALL experience excess outpatient and inpatient activity across their TYA years, which is not related to routine follow-up monitoring. Involving most clinical specialties, associations are striking, showing no signs of diminishing over time. Recognising that all survivors are potentially at risk of late treatment-associated effects, our findings underscore the need to take prior ALL diagnosis into account when interpreting seemingly unrelated symptoms later in life.