In this study, among patients with advanced LC who received platinum-based regimens, the prevalence of grade 0, I, II, and III CIPN–sensory adverse events were 46.2% (n = 43), 36.6% (n = 34), 17.2% (n = 16), and 0% (n = 0), respectively, and the prevalence of grade 0, I, II, and III CIPN–motor adverse events were 52.7% (n = 49), 32.3% (n = 30), 15.0% (n = 14), and 0% (n = 0), respectively. Kautio et al. [33] found that, in patients who received vinca alkaloid, taxane, or platina derivative regimens, 0%, 21%, 42%, and 37% of patients reported a prevalence of grade 0, I, II, and III sensory CIPN adverse events, respectively, and 52%, 31%, 16%, and 1% of patients reported the prevalence of grade 0, I, II, and III motor CIPN adverse events, respectively. The reduced level of neuropathy may result from the fact that patients in Kautio et al. [33] had received 1–3 cycles of treatment, while our subjects had received at least 4 cycles of chemotherapy; indeed, more than half (51.6%) had received 5 or more cycles of treatment, and were still continuing treatment. CIPN symptoms were present within a few days after starting therapy and lasted for several months after beginning treatment. Healthcare providers should seek to detect CIPN early and continue assessment of CIPN as patients continue their chemotherapy.
Our results showed that the average CIPN–related QoL score of patients with advanced LC was 40.44 (SE = 0.57). The level of CIPN–related QoL among subjects in this study was lower than that reported in another recent study [34]. This difference may be due to the different cycles of chemotherapy during which patients were assessed. Patients in our study received an average of 5.53 cycles of chemotherapy and had not yet completed all cycles of chemotherapy, while patients in the study of Ajewole et al. [34] were enrolled within 2 weeks of the first chemotherapy of cycle 1 and followed for 12 weeks after enrollment. These findings may reflect that the impact of CIPN on QoL increases over time. CIPN in advanced LC patients treated with platinum-based chemotherapy may impact their ability to perform self-care, independently complete ADLs, and return to work, as well as their level of physical activity. Healthcare providers should be aware of patients’ reports of outcomes related to CIPN and provide care for their needs.
The most highly rated CIPN items for patients in the present study were: difficulty getting/maintaining an erection, difficulty climbing stairs/rising from a chair, blurred vision, dizziness when standing up from a sitting/lying position, and numbness in the toes/feet. These findings agree with those of previous studies of cancer patients treated with CIPN-related regimens, which indicated that tingling or numbness in the fingers/hands, toes/feet were most the common CIPN–related symptoms, and may limit ADLs and diminish QoL [35,36]. In the present study, difficulty getting / maintaining an erection was the most common problem. Male patients may be embarrassed to discuss their perceptions and feelings about sexual dysfunction. Healthcare providers should therefore actively evaluate each patient’s concerns about changes in sexual function and encourage male patients in particular to express their feelings.
Results of the present study indicated that patients who had a higher level of depression and who had more severe CIPN–sensory scores were more likely to have worse overall QoL. These results are consistent with those of previous studies [37], which reported that CIPN [36] and depression [37] lead to restrictions in ADLs [37] and decreases in mobility and independency [38] in cancer patients treated with platinum-based antineoplastic agents. Healthcare professionals should evaluate neurological function and provide information on nutritional supplements, aerobic exercise, and balance training that may stimulate peripheral neurological function and enhance daily function, to help patients cope with the adverse effects of chemotherapy.
Limitations
This study had several limitations. First, the present study examined patients with advanced LC who received at least 4 chemotherapy cycles, and although such problems may develop as early as 1–2 weeks after initiating treatment, CIPN following chemotherapy cycles is part of a dynamic process that changes over time. Longitudinal studies are needed, with long-term follow up of patients from the time they undergo treatment through the post-treatment period. Second, we did not consider the effect of nutritional supplements (glutathione, glutamine, vitamin E, or B complex) or dietary supplements (vitamins, minerals, proteins, or amino acids) as factors in CIPN, although such factors may affect outcomes. Thus, future studies should extend their analysis to include the use of nutritional supplements. Finally, patients’ initial (pre-treatment) peripheral neurological function and lifestyle, variables not studied here, may have affected the evaluation of CIPN. Further studies are needed to determine the correlation between initial peripheral neurological function, lifestyle, and CIPN.