It is well known that the symptoms of cancer vary depending on the location of the tumor and where it has spread. Less attention has been paid to whether the prevalence of various cancer symptoms has changed over time.
A 17-year study published in the British Journal of General Practice sought to fill this knowledge gap.
The researchers set out to identify the first reported symptoms of probable lung cancer and to see if the percentage of patients with each of the current symptoms changed between 2000 and 2017.
They extracted data from the Clinical Practice Research Data Channel (CPRD) with associated data from the National Cancer Registry and Analysis Service (NCRAS).
The CPRD is defined as a large database of encrypted and anonymous electronic health records created during daily consultations by more than 600 general practitioners in the UK.
Symptoms in patients diagnosed with lung cancer were determined in annual cohorts from January 1, 2000 to December 31, 2017.
The researchers wrote that the percentage of patients with symptoms of shortness of breath, also known as shortness of breath, “increased” over time.
This positive effect was also noted for cough.
The percentage of patients with other symptoms has decreased, especially hemoptysis, also known as coughing up blood and loss of appetite.
The researchers concluded that “for the period 2000-2017. the proportion of patients with lung cancer with symptoms of coughing or shortness of breath has increased, and the proportion of patients with symptoms of hemoptysis has decreased.”
They added: “This trend has implications for medical education and awareness campaigns about the quality of symptoms.”
This study is limited to using coding reading to determine if a patient has experienced symptoms. Reading Codes does not provide information about the duration and severity of symptoms, or whether they were reported by the patient or caused by a physician.
Some patients may be misclassified if symptoms are not recorded in a non-recoverable part of the medical record.
Symptoms described in free text are not available. There is evidence that this may bias estimates in favor of static symptoms such as hemoptysis, which are more likely than “low risk but not free” symptoms to be recorded using codes.
In addition, a small number of patients had a vague primary care presentation with “suspected cancer” or abnormal chest x-ray codes and could not be further classified.
Changes in coding practices and in the characteristics of the general practices that contribute data to the CPRD over time may change estimates of reported symptom prevalence. Reassuringly, the proportion of patients with any reported symptoms was relatively constant over time, indicating that none of these changes were minor.