Association of antipsychotic use with breast cancer: a systematic review and meta-analysis of observational studies with over 2 million individuals

Non-genetic factors and breast cancer: an umbrella review of meta-analyses

BACKGROUND

Previous research has found associations between various non-genetic factors and breast cancer (BrCa) risk. This study summarises and appraises the credibility of the available evidence on the association between non-genetic factors and BrCa risk.

METHODS

We conducted an umbrella review of meta-analyses. Medline, Scopus, and the Cochrane databases were systematically searched for meta-analyses examining non-genetic factors and BrCa incidence or mortality. The strength of the evidence was graded in four categories (i.e., weak, suggestive, highly suggestive, convincing).

RESULTS

A total of 781 meta-analyses from 280 publications were evaluated and graded. We included exposures related to anthropometric measurements, biomarkers, breast characteristics and diseases, diet and supplements, environment, exogenous hormones, lifestyle and social factors, medical history, medication, reproductive history, and pregnancy. The largest number of examined associations was found for the category of diet and supplements and for exposures such as aspirin use and active smoking. The statistically significant (P-value < 0.05) meta-analyses were 382 (49%), of which 204 (53.4%) reported factors associated with increased BrCa risk. Most of the statistically significant evidence (n = 224, 58.6%) was graded as weak. Convincing harmful associations with heightened BrCa risk were found for increased body mass index (BMI), BMI and weight gain in postmenopausal women, oral contraceptive use in premenopausal women, increased androstenedione, estradiol, estrone, and testosterone concentrations, high Breast Imaging Reporting and Data System (BIRADS) classification, and increased breast density. Convincing protective factors associated with lower BrCa risk included high fiber intake and high sex hormone binding globulin (SHBG) levels while highly suggestive protective factors included high 25 hydroxy vitamin D [25(OH)D] levels, adherence to healthy lifestyle, and moderate-vigorous physical activity.

CONCLUSIONS

Our findings suggest some highly modifiable factors that protect from BrCa. Interestingly, while diet was the most studied exposure category, the related associations failed to reach higher levels of evidence, indicating the methodological limitations in the field. To improve the validity of these associations, future research should utilise more robust study designs and better exposure assessment techniques. Overall, our study provides knowledge that supports the development of evidence-based BrCa prevention recommendations and guidance, both at an individual level and for public health initiatives.

TRIAL REGISTRATION

PROSPERO CRD42022370675.

The research trend of hyperprolactinemia from 2011 to 2023 was analyzed by bibliometrics

The objective of this study is to conduct a bibliometric analysis of research trends in hyperprolactinemia from 2011 to 2023. This analysis aims to provide researchers with insights into the current hotspots and frontiers related to hyperprolactinemia. It is worth noting that there are currently no existing reports on bibliometric analyses of hyperprolactinemia. The Social Science Citation Index (SSCI) and Science Citation Index Expanded (SCIE) databases of the Web of Science Core Collection were systematically searched for "articles" and "review articles" related to the topic of hyperprolactinemia from 2011 to 2023. VOSviewer was employed to conduct bibliometric analysis, aiming to analyze the research trends in hyperprolactinemia over the past 13 years. A total of 1865 eligible articles were retrieved, with contributions from 9544 scholars representing 83 countries in the field of research. The United States had the highest number of publications, followed by China. The keywords were categorized into six clusters: (1) etiology of hyperprolactinemia and other related endocrine and metabolic diseases. (2) Hyperprolactinemia and mental illness. (3) Diagnosis and management of hyperprolactinemia. (4) Treatment of hyperprolactinemia and prolactinoma. (5) Detection of macroprolactin and macroprolactinemia. (6) Symptoms of male hyperprolactinemia. Over the past 13 years, there has been a consistent and slightly increasing trend in the number of research papers focusing on hyperprolactinemia. The primary areas of research focus are centered around the diagnosis and treatment of hyperprolactinemia caused by antipsychotic drugs or prolactinoma.

The incidence risk of gynecological cancer by antipsychotic use: a meta-analysis of 50,402 patients

BACKGROUND

Female gynecological cancers represent a serious public health problem, with 1,398,601 new diagnoses and 671,875 deaths per year worldwide. Antipsychotics are often used in psychiatric disorders, including schizophrenia, bipolar disorder, and major depression. It is estimated that the prescription of these drugs is linked to 1,800 deaths a year in the United States, but their association with cancer remains controversial.

METHODS

We searched PubMed, Scopus, and Web of Science databases for studies reporting the correlation in the incidence risk of gynecological cancer by antipsychotic use. We used DerSimonian and Laird random-effect models to compute logit transformed odds ratio (OR) for the primary binary endpoint with 95% confidence interval (CI). Heterogeneity was assessed through effect size width along with I-squared and Tau-squared statistics. Review Manager 5.4.1. was used for statistical analyses. A p-value of < 0.05 denoted statistically significant.

RESULTS

50,402 patients were included, of whom 778 (1,54%) took antipsychotic medication for at least 1 year. 1,086 (2,15%) with ovarian cancer and 49,316 (97,85%) with endometrial cancer. Antipsychotic use (OR 1.50; 1.06 to 2.13 95% CI; p-value 0.02), hypertension (OR 1.50; 95% CI 1.06 to 2.13; p-value < 0.01), nulliparity (OR 1.98; 95% CI 1.53 to 2.57; p-value < 0.01) and multiparity (OR 0.53; 95% CI 0.41 to 0.69; p-value < 0.01) showed significantly different distributions between groups of cancer and cancer-free patients. The primary endpoint of incidence risk of gynecological cancer by antipsychotic therapy showed a statistically significant difference (OR 1.67; 95% CI 1.02 to 2.73; p-value < 0.05) against the use of antipsychotic drugs.

CONCLUSIONS

Our meta-analysis showed that the use of antipsychotic drugs increases the risk of gynecological cancers, particularly endometrial cancer. This result should be weighed against the potential effects of treatment for a balanced prescribing decision.

Antipsychotic Use and Risk of Breast Cancer in Women With Severe Mental Illness: Replication of a Nationwide Nested Case-Control Database Study

BACKGROUND AND HYPOTHESIS

Breast cancer is more prevalent in women with severe mental illness than in the general population, and use of prolactin-increasing antipsychotics may be a contributing factor.

STUDY DESIGN

A nested case-control study was conducted using the Swedish nationwide registers (inpatient/outpatient care, sickness absence, disability pension, prescribed drugs, cancers). All women aged 18-85 years with schizophrenia/schizoaffective/other nonaffective psychotic disorder/bipolar disorder and breast cancer (cases) were matched for age, primary psychiatric diagnosis, and disease duration with five women without cancer (controls). The association between cumulative exposure to prolactin-increasing/prolactin-sparing antipsychotics and breast cancer was analyzed using conditional logistic regression, adjusted for comorbidities and co-medications.

STUDY RESULTS

Among 132 061 women, 1642 (1.24%) developed breast cancer between 2010 and 2021, at a mean age of 63.3 ± 11.8 years. Compared with 8173 matched controls, the odds of breast cancer increased in women with prior exposure to prolactin-increasing antipsychotics for 1-4 years (adjusted odds ratio [aOR] = 1.20, 95% confidence interval [CI] = 1.03-1.41), and for ≥ 5 years (aOR = 1.47, 95%CI = 1.26-1.71). There were no increased or decreased odds of breast cancer with exposure to prolactin-sparing antipsychotics of either 1-4 years (aOR = 1.17, 95%CI = 0.98-1.40) or ≥5 years (aOR = 0.99, 95%CI = 0.78-1.26). The results were consistent across all sensitivity analyses (ie, according to different age groups, cancer types, and primary psychiatric diagnosis).

CONCLUSIONS

Although causality remains uncertain, exposure to prolactin-elevating antipsychotics for ≥ 1 year was associated with increased odds of breast cancer in women with severe mental illness. When prescribing antipsychotics, a shared decision-making process should consider individual risk factors for breast cancer.

The causal relationship of colorectal cancer on schizophrenia: A Mendelian randomization study

Comorbidities associated with psychiatric disorders often occur in patients with cancer. A causal effect of schizophrenia on cancer was observed using Mendelian randomization (MR) analysis. However, the causal effect of colorectal cancer on schizophrenia has not been studied using MR analysis. Therefore, we performed MR analysis to investigate the causal effects of colorectal cancer on schizophrenia. We performed "two-sample summary-data Mendelian randomization" using publicly available genome-wide association studies data to investigate the causal relationship between colorectal cancer (as exposure) and schizophrenia (as outcome). The inverse variance weighted method was used to calculate causal estimates. In 2 TSMR analyses, we reported that the odds ratios for schizophrenia per log odds increase in colorectal cancer risk were 6.48 (95% confidential interval [CI] of OR 1.75-24.03; P = .005) and 9.62 × 106 (95% CI of OR 1.13-8.22 × 1013; P = .048). Pleiotropic tests and sensitivity analysis demonstrated minimal horizontal pleiotropy and robustness of the causal relationship. We provide evidence for a causal relationship between the incidence of colorectal cancer and the development of schizophrenia through TSMR analysis.

Breast cancer risks following antipsychotic use in women with bipolar disorder versus schizophrenia: A territory-wide nested case-control study spanning two decades

Accrued epidemiologic data largely support an association of antipsychotic use with breast cancer in women with schizophrenia. No studies have specifically investigated such risks in women with bipolar disorder. This study aims to examine the association between antipsychotics and breast cancer in women with bipolar disorder and compare it against schizophrenia. We conducted a nested case-control study using a territory-wide public healthcare database in Hong Kong examining women aged ≥18 years with bipolar disorder or schizophrenia. Using incidence density sampling, women with a breast cancer diagnosis were matched by up to 10 control participants. In total, 672 case participants (109 with bipolar disorder) and 6,450 control participants (931 with bipolar disorder) were included. Results show a significant association of first-generation antipsychotics with breast cancer in both women with schizophrenia [adjusted odds ratio (aOR) 1.49, 95% confidence interval (CI) 1.17-1.90] or bipolar disorder (aOR 1.80, 95% CI 1.11-2.93). Second-generation antipsychotics was associated with breast cancer only in women with bipolar disorder (aOR 2.49, 95% CI 1.29-4.79), with no significant association found in women with schizophrenia (aOR 1.10, 95% CI 0.88-1.36). In conclusion, further research on breast cancer risks is warranted for women with bipolar disorder on antipsychotics.

Antipsychotic exposure is an independent risk factor for breast cancer: A systematic review of epidemiological evidence

Background

The effect of antipsychotics on breast cancer remains controversial.

Materials and methods

Embase, Scopus, PubMed, Web of Science, Cochrane Library, and Hebei Medical University Library were used for the literature search. Observational studies with original data for the effects of antipsychotics on breast cancer were used. Studies of bed quality, those with inadequate sample size, incomplete follow-up works, or studies that did not meet the criteria were excluded. Meta-analysis was performed using R version 4.1.2. The odds ratio (OR) and its 95% confidence interval (CI) were used to evaluate the proportion of breast cancer in different groups. To detect possible sources of heterogeneity, subgroup and meta-regression analyses were employed.

Results

Pooled data from 11 relevant studies with 1,499,001 participants suggested that individuals exposed to antipsychotics were more likely to suffer from breast cancer than those who were not exposed (OR, 1.23; 95% CI, 1.04-1.47). No significant difference in breast cancer prevalence between the atypical and typical antipsychotic groups was found (OR, 1.23; 95% CI, 0.93-1.63). Prolactin (PRL)-increasing and PRL-sparing antipsychotics posed a similar risk of breast cancer (OR, 1.13; 95% CI, approximately 0.97-1.31). Furthermore, the use of antipsychotics is attributed to increased mortality in patients with breast cancer (OR, 1.54; 95% CI, 1.29-1.82). Those exposed to antipsychotics at the maximum dose were more likely to suffer from breast cancer than those exposed to the minimum dose.

Conclusions

Antipsychotic exposure is an independent risk factor for breast cancer. No significant difference in the risk of breast cancer between typical and atypical antipsychotics was noted. Those exposed to antipsychotics at higher doses are more likely to suffer from breast cancer. Moreover, the use of antipsychotics is attributed to increased mortality in patients with breast cancer. PRL-increasing and PRL-sparing antipsychotics pose a similar risk of breast cancer.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022307624.

Mortality in Schizophrenia-Spectrum Disorders: Recent Advances in Understanding and Management

Schizophrenia is a life-shortening disease and life expectancy in patients may be 15-20 years shorter than in the general population, with increasing longevity gap over time. Premature mortality in schizophrenia-spectrum disorders is mainly due to preventable natural causes, such as cardio-vascular disease, infections, respiratory tract diseases and cancer, alongside suicide, homicide and accidents. There is a complex interplay of factors that act synergistically and cause physical morbidity to patients and subsequent mortality. Smoking, alcohol/substance abuse and sedentary life style, alongside disease-related factors, such as metabolic abnormalities and accelerating aging contribute to physical morbidity. Moreover, the symptomatology of psychosis and stigma may limit patients' access to quality medical care. Interventions to promote physical health in those patients should be multifaceted, and should target all patient-related modifiable factors, but also should address service-related healthcare disparities. Long-term antipsychotic use (including clozapine and long-acting injectables) is associated with substantially decreased all-cause mortality, including suicide and cardiovascular mortality, in patients with schizophrenia despite the well-known cardiometabolic adverse effects of second-generation agents. Integrated care may involve co-location of physical and mental health services, liaison services, shared protocols and information sharing systems, and has emerged as a way to address the physical health needs of those patients. Interventions to address mortality in schizophrenia and related syndromes should take place as early as possible in the course of the patients' treatment, and could be an integral component of care delivered by specialized early intervention services.