Results from a systematic review and comparative meta-analysis show that despite increased mortality from cancer in people with mental illness, this population receives less cancer screening compared to the general population. These findings were published by Solmi et al in The Lancet Psychiatry.
The research team wrote that people with mental illness are more likely to die from cancer. Their goal was to assess whether people with mental illness undergo less cancer screening compared with the general population.
Meta-Analysis Methods
In the systematic review and meta-analysis, researchers searched PubMed and PsycINFO (without a language restriction) and hand-searched the reference lists of included studies and previous reviews for observational studies from database inception until May 2019.
They included all published studies focusing on any type of cancer screening in patients with mental illness, as well as studies that reported prevalence of cancer screening or comparative measures between patients with mental illness and the general population.
The primary outcome was odds ratio (OR) of cancer screening in people with mental illness vs the general population. The Newcastle-Ottawa Scale was used to assess study quality and I2 to assess study heterogeneity.
In total, 47 publications provided data from 46 samples, which included 4,717,839 individuals (501,559 patients with mental illness and 4,216,280 controls), of whom 69.85% were women. Data was provided for:
- Breast cancer screening (κ = 35; 296,699 individuals with mental illness and 1,023,288 in the general population)
- Cervical cancer screening (κ = 29; 295,688 with mental illness and 3,540, 408 in the general population)
- Colorectal cancer screening (κ = 12; 153,283 with mental illness and 2,228,966 in the general population)
- Lung and gastric cancer screening (both κ = 1; 420 with mental illness and none in the general population)
- Ovarian cancer (κ = 1; 37 with mental illness and none in the general population)
- Prostate cancer (κ = 6; 52,803 with mental illness and 2,038,916 in the general population).
Median quality of the included studies was high, at 7 (IQR 6–8).
Findings
Screening was significantly less frequent in people with any mental disease compared with the general population for any cancer (κ = 37, OR = 0.76, I2 = 98.53%, with publication bias of Egger’s P value = .025), breast cancer (κ = 27, OR = 0.65, I2 = 97.58% and no publication bias), cervical cancer (κ = 23, OR = 0.89, I2 = 98.47% and no publication bias), and prostate cancer (κ = 4, OR = 0.78, I2 = 79.68% and no publication bias), but not for colorectal cancer (κ = 8, OR = 1.02, I2 = 97.84% and no publication bias).
The study team concluded that despite increased mortality from cancer in people with mental illness, this population receives less cancer screening compared with that of the general population. They mentioned that specific approaches should be developed to assist people with mental illness in undergoing appropriate cancer screening—especially women with schizophrenia.
Disclosure: For full disclosures of the study authors, visit thelancet.com.
