Sample and treatment
Between January 2005 and August 2010, 988 men underwent RALP as primary treatment for PCa at Oslo University Hospital, Radiumhospitalet. By March 2011 six men had died, and a questionnaire was mailed to the remaining 982 patients, and 777 responded (79% response rate). An attrition analysis between the respondents and the 205 non-respondents showed no significant differences on PCa-related and surgical variables except that the non-respondents were younger and had higher Clavien sum scores for operative complications . Forty-seven responders were not included in our analysis due to incomplete data on current WA, leaving 730 men as our study sample.
Patients were operated with the same technique during all years (2005–2010), the Vattikutti technique, also described and published by our group [10, 11]. The principles of this technique are basically used in the majority of centers operating RALP. The follow-up of patients has been consistent and equal for all patients in the study period and thereafter.
Current WA compared to the lifetime best WA was self-rated on a 10-point numerical rating as previously decribed [3,4,5]. We dichotomized the current WA scores into high WA (score 8–10) versus moderate/low WA (score 0–7).
Anxiety and depression
The Hospital Anxiety and Depression Scale (HADS) covers the last 7 days. Both the depression and the anxiety subscales have 7 items scored on a 4-point scale from 0 (‘not present’) to 3 (‘considerable’), with subscale sum scores ranging from 0 to 21. The cut-off scores for clinical anxiety and depression is a sum score ≥ 8 [11, 12]. Cronbach’s coefficient alpha was 0.85 for the anxiety and 0.79 for the depression subscale.
Neuroticism was self-rated on an abridged version of The Eysenck Personality Inventory (EPQ) for trait affects with six items each scored as present (1) or absent (0) . The sum score ranged from 0 to 6, and was dichotomized into high (sum score 3–6) and low neuroticism (sum score 0–2) according to Grav et al. . Cronbach’s alpha was 0.78.
The EPIC-26 is a self-report instrument for rating of typical AEs of the last 4 weeks covering the urinary, bowel, sexual, and hormonal domains after PCa treatment. While the urinary and sexual domains cover both function and bother, the bowel and hormonal ones cover only bother. The scores are converted from 0 (worst) to 100 (best) and group means are calculated [15, 16].
Among PCA-related variables pre-treatment risk groups were defined according to D’Amico et al. . Biochemical PSA relapse, post-RP radiotherapy, and hormone treatment after RALP were self-reported, and defined as PCa treatment failure.
Men were either married or cohabiting or were not living with a partner. Non-employed status concerned men who were without paid work or pensioned. Low level of education was defined as ≤12 school years completed versus high level (> 12 years). Comorbidity was based on self-report of stroke, diabetes, chronic obstructive lung diseases, liver disease, arthrosis, rheumatic diseases (all 1 point), and kidney disease (2 points) based on illness points according to Charlson et al. .
Descriptive statistics were performed with chi-square tests for categorical variables and independent sample t-tests for continuous variables, but with Mann-Whitney U-tests in case of skewed distributions. One-sample t-tests were used to compare the current WA mean score of our sample with that of other published samples.
To find the p-value adjusted for age, we used multivariate logistic analyses for categorical data, and multilinear linear analyses for continuous data. These statistical procedures were performed for each of the age-relevant independent variables with Low/moderate WA versus High WA (reference) as dependent variable.
Univariate and multivariable logistic regression analyses with relevant independent variables and moderate/low WA as outcome variable and high WA as reference were performed. The strength of associations was described by odds ratios (ORs) with 95% confidence intervals (95%CI). The level of significance was set at p < 0.05, and all tests were two-sided. Data analyses were performed with IBM SPSS version 25.0 for PC (IBM, Armonk, NY).