Urolithiasis may be a chronic condition, occasionally characterized by disruptive episodes such as acute renal colic, acute kidney injury, and fever, that may involve Emergency Department (ED) visits and subsequent medications and surgical procedures, hence a significant negative impact on the patient’s health-related quality of life (HRQOL) may be implied.1
In this context, the use of tools able to assess quality of life (QOL) find their rationale, in particular questionnaires, that may be simple, not-expensive, self-administered instruments. The Wisconsin Stone Quality Of Life Questionnaire (WISQOL) is a disease-specific questionnaire, created for kidney stones patients, nowadays validated in several languages. It’s made up of 28 items exploring disease, social, vitality, and emotional impact of kidney stones in reference to the last 4 weeks, maximum total score is 140; higher final scores correspond to better HRQOL.2
Our group double-back translated the original version in Italian, we submitted the obtained questionnaire to a pilot group of 10 patients and then we extended the final version to kidney stones former patients, both symptomatic and asymptomatic, referring to an outpatient setting of two stone clinics in Rome, both at high volume for kidney stones treatments. From January 2020 to January 2021 we included 93 native-Italian speakers, at least aged 18 and who attended the elementary school or higher grade. We didn’t enroll patients presenting with mental impairment. They completed the I-WISQOL and the SF-36 questionnaire, a general health-related questionnaire already well validated.3
Apart from the descriptive analysis, internal consistency of the I-WISQOL was obtained with Cronbach’s α. The Spearman test was used for item and domain correlations and I-WISQOL total score. Correlation of total scores of the I-WISQOL and SF36 was assessed to determine convergent validity. Correlations between clinical variables and results from the I-WISQOL were analyzed to descriptively assess the association of interest. Differences among the population were assessed (ANOVA). Multivariate linear regression analysis was performed to identify predictors of Wisconsin's total score.
The majority of patients were male (56%), 84.9% were recurrent stone formers, 46% of patients were symptomatic and the mean time since initial stone onset was 13.1 (13.7 SD), 67.74% reported 1 to 2 previous Emergency Department (ED) visits, and the main surgical treatment referred from the population were Lithotripsy (External Shock Wave Lithotripsy - ESWL) and ureterolithotripsy (ULT), 40.86% and 24.73%, respectively.3
Mean I-WISQOL total score was 101.6 ± 22.7 S.D., while the SF-36 total score was 63.8 ± 19.7. Our analysis showed high internal consistency (Cronbach’s α: 0.95), while the Spearman rank correlation test showed a good correlation between SF-36 and I-WISQOL total scores (r = 0.70, p<0.001).3
We observed some statistically significant differences in total I-WISQOL scores, in particular, we found lower total scores according to the increasing number of ED visits and hospitalizations (p=0.037 and p=0.025, respectively). Moreover, a significant difference was noted according to the main surgical treatment received (ESWL vs RIRS/URS vs PCNL, p=0.043), in particular patients who underwent PCNL totalized lower scores.3
We interpreted these results in terms of burden of disease and aggressiveness of treatments; in other words, we postulated that patients with the need for hospitalization and more invasive procedures may be more afflicted by the disease and perceive a worse QOL than others.
At multivariate analysis we considered some of the elements which may influence and predict a worse QOL; interestingly, only the number of renal colic episodes and hospitalization were associated with a statistically significant decrease in I-WISQOL total score (p=0.014 and p=0.042, respectively). These results may be interpreted in line with the previous analysis, patients referring more often to the medical center may present a worse QOL as regards kidney stones, since they may feel their condition is more precarious and dangerous than individuals with a more symptomatic episode but limited to a shorter amount of time. Regardless of the WISQOL referred to the last 4 weeks, patients with a long past history of kidney stones may complain of a worse QOL; few studies analyzed this subtle aspect of the disease, as Tapiero et al.4
Compared with this study,4 we performed a correlation analysis between QoL and single factors (i.e. renal colic events, number of stone-related procedures, number of ER visits, and number of inpatient hospitalization events) to understand better which factor in the natural history of the disease affect more patients’ QoL. Interestingly, our analysis using a linear regression model showed that only renal colic (p=0.042) and inpatient hospitalization (p=0.006) were independently associated with a decline in QoL. Interestingly, the number of stone-related procedures was not significantly associated with an impaired QoL (p=0.243) suggesting that surgical procedures that require both outpatient and inpatient hospitalization are well tolerated by the patient rather than symptoms.
Considering the different kidney stones clinical presentations, in our hypothesis a disease-specific questionnaire may be a valid instrument, i.e. to objectify stones' impact on QOL in order to help clinicians to choose the right management for each patient better.
Moreover, we may suggest that using a validated questionnaire to assess a specific disease-related QOL, may reveal a useful tool to objectively compare the impact of i.e. different surgical treatments on patients in different studies.
Written by: Martina Moriconi, Alessandro Sciarra, Giovanni Battista Di Pierro, Stefano Salciccia
Department of Maternal-Infant and Urological Sciences, Umberto I Policlinic Hospital, Sapienza University, Rome, Italy
References:- Tzelves, L., Türk, C. & Skolarikos, A. European Association of Urology Urolithiasis Guidelines: Where Are We Going? Eur Urol Focus 7, 34–38 (2021).
- Penniston, K. L. & Nakada, S. Y. Development of an instrument to assess the health-related quality of life of kidney stone formers. J. Urol. 189, 921–930 (2013).
- Salciccia, S. et al. Translation and validation of the Italian version of the Wisconsin Stone Quality of Life Questionnaire (I-WISQOL) for assessing the quality of life in patients with urolithiasis. Minerva Urol Nephrol (2023) doi:10.23736/S2724-6051.23.04882-6.
- Tapiero, S. et al. The impact of the number of lifetime stone events on quality of life: results from the North American Stone Quality of Life Consortium. Urolithiasis 49, 321–326 (2021).