Delayed diagnosis of multiple conditions a real possibility with COVID-19

The COVID-19 pandemic may have caused missed or delayed diagnosis of many medical conditions, according to a UK-based retrospective study of general practice (GP) utilization.

The researchers sourced primary care data from 47 GP practices recorded in the Salford Integrated Record database between January 2010 and May 2020 comprising a socioeconomically deprived urban population of 241,458 people (mean age 35 years, 49 percent female).

Compared with the expected numbers based on previous years, there was a 50 percent (95 percent confidence interval [CI], 41.1–56.9) drop in the rates of first diagnoses of common mental health problems in March–May 2020 (1,073 reported vs 2,147 expected cases). [Lancet Public Health 2020;doi:10.1016/S2468-2667(20)30201-2]

Diagnosis of circulatory system diseases (cardiovascular and cerebrovascular disease) reduced by 43.3 percent (95 percent CI, 29.6–53.5, representing 456 fewer diagnoses than expected), while diagnosis of type 2 diabetes reduced by 49 percent (95 percent CI, 23.8–63.1, representing 135 fewer diagnoses).

First prescriptions for common medications used to treat these conditions were also lower than expected over the time frame. There was a 39.1 percent (95 percent CI, 24.3–49.5) reduction in first prescriptions for selective serotonin reuptake inhibitors and a 35.7 percent (95 percent CI, 14.1–49.5) reduction in first metformin prescriptions compared with expected numbers. First prescriptions for aspirin (75 mg), calcium channel blockers, angiotensin-converting enzyme inhibitors, and clopidogrel reduced by 29.3, 35.6, 52.0, and 44.2 percent, respectively.

Overall cancer diagnoses reduced by a nonsignificant 16 percent (95 percent CI, -18.1 to 36.6, representing 31 fewer diagnoses). The lack of significance may be due to presentation of “only the most serious cases, and therefore individuals most likely to receive a positive diagnosis,” said the researchers.

In addition, there may be a time lag between cancer diagnosis in secondary care and inclusion in primary care record. This may be explained by the significant 44.1 percent (95 percent CI, 22.4–57.8) reduction in cancer diagnosis in May 2020, they said.

Due to the gradual development of most of the diseases investigated in this study, the researchers ruled out a reduction in disease incidence due to changing patterns of behaviour during the pandemic.

“[T]he reduced number of new diagnoses observed when compared with the expected numbers … most likely … represent a large number of true disease cases that have gone undetected, undiagnosed, and untreated,” they said. However, they acknowledged that the high deprivation and premature mortality rates in Salford preclude generalization of the findings to other cities.

Post-pandemic outlook

“When frequency of engagement with health services increases again, through less widespread fear of contracting COVID-19 in a healthcare facility or because patients’ symptoms have become intolerable, presentation rates for [these] conditions … might markedly increase,” the researchers cautioned. “The delay in diagnoses is also likely to have implications for the severity of these conditions when patients present.”

“Primary and secondary healthcare services, and specialist mental health services and counselling services, should prepare for an increase in demand … and take steps to prioritize patients with delayed diagnoses,” they said. This would be crucial to prevent “the backlog [that] could plausibly overwhelm primary and secondary healthcare services.”

“If a similar emergency occurs in the future, steps should be taken to mitigate these indirect effects,” the researchers advised. This includes ensuring continuing use of health services by patients and encouraging widespread use of telehealth services.