Prostate cancer (PCa) in Europe is expected to account for 25% of worldwide PCa cases followed by the United States with 23%, according to 2018 GLOBOCAN estimations for 2020-2040 period (1,2). Curative treatment options for PCa include active surveillance in low-risk patients, surgery techniques and hormonal treatment among other choices (3).

Robotic, Laparoscopic and Open Radical Prostatectomy (ORP) included complications as postoperative infections, urinary incontinence or erectile dysfunction that may be worse in men with type 2 diabetes mellitus (T2DM) (4,5). This clinical observation is supported by recent meta-analyses (6) which indicate that preexisting diabetes in cancer patients significantly elevates the risk of surgical and postoperative complications compared to those without the disease. The literature indicates that surgical interventions involve inherent risks such as postoperative infections, blood loss requiring transfusion and urological infection (7). This is associated with increased use of healthcare services and prolonged hospital stays.

PCa and T2DM are linked through complex molecular interactions that worsen prognosis. The Insulin-like growth factor 1 axis, frequently altered in diabetic states, interacts with androgen signaling to regulate the cell cycle and cellular survival. This interaction may facilitate both androgen-dependent and androgen-independent tumorigenesis through autocrine and paracrine mechanisms. Ultimately, these pathophysiological pathways promote oncogenic transformation, highlighting potential therapeutic targets (8).

These molecular interactions highlight the clinical importance of T2DM in PCa progression. Consequently, this study aims to describe trends, national PCa rates, in-hospital outcomes of admissions and sociodemographic and clinical characteristics of men with and without T2DM that were hospitalized for PCa.

Using the Minimum Basic Data Set (MBDS), a prospective observational study has been carried on. The MBDS is a database provided by the Ministry of Health, Consumer Affairs, & Social Welfare. Information about MBDS is available online (9).

Primary and secondary diagnoses were coded according to the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9CM), which was used until 2015 (10). The database was defined by the presence of the following codes in the primary diagnosis field, the codes ICD-10CM 185 and 233.4, corresponding to “Malignant neoplasm of the prostate” and “Carcinoma of the prostate in situ”, respectively. The period of the study was from 2005 to 2015.

The sample was stratified according to the presence of a previous diagnosis of T2DM (codes ICD-9 CM: 250.X0 y 250.X2) prior to admission. Cases ≥ 40 years old were selected (144,210 cases).

Incidence rates were expressed per 100,000 inhabitants using the Spanish male population for nonT2DM cases provided by Spanish national Statistics Institute (11) and the prevalence described by di@bet.es (12) study for T2DM group.

Vascular Risk Factors (VRF), intercurrent illnesses (defined as conditions occurring simultaneously with PCa) and complications included were the following: Hypertension (ICD-9-CM code:401); obesity (ICD-9-CM codes 278.00 and 278.01); impaired lipid metabolism (ICD-9-CM codes: 272.0; 272.1 and 272.4); tobacco smoking (ICD-9-CM codes: 305.1 and V15.82); prostatitis (ICD-9-CM codes: 601.X); elevated prostate-specific antigen (PSA) levels [PSA] (ICD-9-CM code: 790.93); Malignant neoplasm of bone and marrow secondary (ICD-9-CM code: 198.5); postoperative bleeding in prostate surgery (ICD-9-CM code: 60.94); transfusion of packed red blood cells (ICD-9-CM code: 99.04); postoperative infections (ICD-9-CM code: 40.29). Comorbid conditions were classified using the Charlson Comorbidity Index (CCI) in three categories (0, 1 and 2: no comorbidity, moderate and high comorbidity). T2DM and PCa were not included in the CCI.

Outcomes analysed were length of stay, prolonged length of stay (length of hospital stay over percentile 75) and exitus. Analysis comparing both groups of men with and without T2DM were carried out.

Continuous variables were expressed as mean with standard deviation (SD) and categorical variables as proportions. Bivariate analysis was performed to assess possible associations between qualitative variables was performed using Pearson's Chi-square test. Binary logistic regression was performed, with in-hospital mortality (IHM) as the dependent variable.

A total of admissions related to PCa from 2005 to 2015 were 144,210 cases. Men with T2DM accounted for 13% (18,725 cases). The mean age of the total sample was 67.65 ± 8.99 years old. T2DM men were older (p < 0.001). The mean length of stay for the total sample was 6.58 ± 7.62 days. A significant difference was observed between T2DM cases and non T2DM men: 7.1 ± 8.13 days versus 6.50 ± 7.54 respectively (p < 0.001). Regarding prolonged stay (stay > 8 days), a statistically significant difference was found between the groups, being higher in T2DM cases (28.7% vs. 25.2%; p < 0.001)

Discharge home accounted for 92.6% in subjects without T2DM compared to 90% in cases with T2DM. Exitus reached 612 (0.5%) and 154 cases (0.8%) (. < 0.001) in cases without T2DM and with T2DM, respectively. Admission trends for PCa among with and without T2DM groups showed an upward trend from 2005 to 2011 (Figure 1).

Figure 1. Figure 1. Annual hospital admission rates per 100,000 men over the study period, comparing total admissions (solid black line) with admissions among patients with type 2 diabetes mellitus (T2DM; dashed red line)

Prevalence of VRF was higher (p< 0.001) in T2DM group with hypertension being the most prevalent vascular risk factor (Table 1).

Table 1. Table 1. Clinical characteristics of admissions related to prostate cancer of men with and without type 2 diabetes mellitus (TDM2)

Surgical procedures were described in Table 2. Radical prostatectomy was the most commonly used technique. In reference to transfusion of packed red cells, it was higher in T2DM group (7.6% vs. 5.9%; p < 0.001)

Table 2. Table 2. Procedures in admissions related to prostate cancer admission in population with and without type 2 diabetes mellitus

In logistic binary regression, T2DM and prolonged stay hospital were associated with a higher likelihood of IHM (OR = 1.32; IC95% = 1.09-1.59; p = 0.003 and OR = 3.25; IC95% = 2.79-3.78; p < 0.001). The oldest age group (≥80 years old) and the highest level of CCI also described the highest likelihood to IHM (Table 3).

Table 3. Table 3. Binary logistic regression for the effect of vascular risk factors and other variables on in-hospital mortality in admissions for prostate cancer in men with and without type 2 diabetes mellitus

The proportion of discharges among men with T2DM (13%) during the period of study is consistent with the prevalence of T2DM described by di@bet.es study (12) (13.8%). Similarly, the Bogotá Population Survey (13) (2022–2023; published in 2024) reported a prevalence of 11.0% (95% CI = 9.0–13.5%) and the Colombian Study of Nutritional Profiles Study (14) (carried out in 2018; published in 2021), conducted in 736 adults across five main cities, reported a prevalence of 10.1%. Taken together, these findings indicate that T2DM prevalence exceeds 10% across international studies, in line with the observed proportion of hospital discharges of this study.

Prevalence of VRF is higher among T2DM cases, a finding that is consistent with other European studies (15,16) that highlights the prevalence of VRF and major cardiovascular disease among T2DM population. Hypertension is the VRF with the highest proportion of cases in both groups of samples (with and without T2DM), representing a condition associated with an increased risk of cardiovascular diseases (17). Prolonged hospitalization among T2DM men has 2.35-fold increase the risk of IHM, worsen outcomes and risen hospitalization costs that could be preventable through intensive control health programmes worldwide.

Obesity is other VRF with a relevant prevalence in T2DM individuals, this may strengthen the association between T2DM and IHM in PCa admissions. Kelkar et al (15) described the coexistence of obesity and T2DM related to specific mortality of PCa. Furthermore, obesity and metabolic syndrome increase the risk of post-surgical complications (4), i.e. the need for transfusion as it is described in this study in the group of T2DM men. On the other hand, the protective rol described in logistic binary regression in reference to obesity, although non statistically significance, suggests the existence of the “obesity paradox” (18) among the men with T2DM and obesity (cases of exitus among leaner T2DM men accounted for 149 and 0.8%, vs. the 5 exitus and 0.5% cases in the group of T2DM with obesity). This finding supports the need for strategies to moderate mortality risk in T2DM population with obesity.

As previously noted, obesity is a critical clinical determinant that increases the likelihood of requiring transfusion (4). This greater technical complexity may partly explain the higher demand for packed red blood cell transfusions observed in patients with T2DM (7.6% vs. 5.9%; p < 0.001), reinforcing the evidence that an adverse metabolic profile is associated with early complications during hospitalization for PCa. Supporting these findings, recent research by Deol et al. (19) carried out in 2025 reported that obesity is associated with increased estimated blood loss, longer operative times, and higher early complication rates. Collectively, these findings underscore the need for specialized, multidisciplinary perioperative management in the acute hospital setting to address the vulnerabilities of patients with T2DM and related comorbidities.

A major strength of this study lies in the use of a standardized database that has been used previously and the large size of the sample (20). However, this study has several limitations. The database lacks detailed clinical information on PCa severity, as well as on the duration and level of glycemic control in patients with T2DM, which may limit the depth of the analysis. A notable limitation arising from the structure of the MBDS is the absence of variables such as glycemic control indicators and disease duration. This is relevant because preoperative metabolic status is a key determinant of postoperative outcomes. For instance, preoperative HbA1c levels ≥6.5% have been independently associated with worse oncological outcomes and poorer recovery of urinary continence after radical prostatectomy (21). Although the lack of granular data prevents a precise assessment of the specific impact of glycemic control and T2DM duration, the observed 1.32-fold increase in in-hospital mortality remains a robust finding. This association highlights T2DM as a critical determinant of patient outcomes, even though the extent to which inadequate glycemic control contributes to this risk cannot be fully quantified with the available data. Consequently, our results underscore the clinical vulnerability of this population, while suggesting that future studies incorporating more detailed clinical variables could further refine the understanding of these outcomes.

Mortality predictors for IHM in PCa are the presence of T2DM, higher age, higher CCI and prolonged hospital stay. These results indicate worse outcomes and higher risk of IHM of T2DM men hospitalized for PCa.

Ethical approval and informed consent statements: The study was conducted using anonymized data from the Minimum Basic Data Set (MBDS), and thus did not require ethical committee approval or informed consent.

Data availability statement: Data are available to researchers upon request through an online application to the Ministry of Health of Spain.

The author received no financial support for the research, authorship, and/or publication of this article.

The author declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.