The associations of insulin injection omission with other health conditions were examined. Surprisingly, history of depression was not associated with insulin omission; this contradicts findings from studies of general adherence and of insulin omission among adolescents. However, because current depression was not assessed, any concurrent association was likely to be lost. Others have shown that depression symptom scores fluctuate substantially over relatively short periods of time; individuals with elevated depression symptoms at a given point in time are likely to not report elevated symptoms 6 months later. In addition, depression symptoms across the whole range of severity symptoms have been shown to predict regimen adherence more powerfully than diagnosed depression. Being disabled was associated with less insulin omission; this may be due to a variety of reasons, including their receiving more assistance with care, or making a greater effort to compensate for poor health.
Two aspects of patients’ treatment regimens were associated with increased insulin omission—respondents who took more injections each day and those who did not follow a healthy diet were more likely to skip injections. That dietary nonadherence is associated with insulin nonadherence is not surprising. More frequent injection omission among individuals taking more injections could reflect the frequently reported finding that more complex regimens are associated with lower levels of adherence. It might also be that the impact of skipping a shot is reduced among individuals who take more shots.
Insulin and injection-related factors
Our study suggests that insulin omission is affected by the perceived burden of insulin therapy (i.e., having to plan one’s life around insulin injections and feeling that the insulin regimen interferes with activities of daily living such as social activities, work-related activities, and family care-giving responsibilities). We offer one caveat regarding our findings; we do not believe that the behavior of planning one’s day around insulin injections actually increases the level of insulin injection omission, but we do believe that feeling that one has to plan around one’s injections is associated with higher frequency of skipping insulin injections one should take. That is, when there is a conflict between scheduling of treatment and life activities, one can either plan one’s activities in a way that reduces this conflict or deal with the conflict by ignoring treatment needs. Reducing the perceived burden of insulin injections may require more effort from health care providers. As we have suggested elsewhere, providers must find out what the specific issues are for each patient and work with that patient to develop solutions that will work for him or her.
We note that the measure of interference with eating and exercise was significantly associated with insulin injection omission until interference with activities of daily living was entered into the model (results not shown). Thus, while interference with eating and exercise might be part of the burden of insulin therapy, interference with other aspects of daily living had a more substantial association with insulin omission.
Our study suggests that insulin omission may be affected by the immediate experience of injecting insulin as painful and embarrassing (but not dissatisfaction with time needed, ease of use, or skin inflammation/bruising). There are numerous device-related strategies for reducing pain and embarrassment, including insulin pens, finer gauge needles, injection ports, needleless injectors, and other injection assistance devices. However, we have found that patients do not feel that their health care providers are giving them adequate assistance in managing these problems, even when they raise the issue with their providers.
We note that the measure of negative affect toward injections was significantly associated with insulin omission until dissatisfaction with injection embarrassment and pain were entered into the model (results not shown). This suggests that addressing pain and embarrassment may reduce not only insulin omission, but also the emotional burden of injections, thereby enhancing psychological well-being. It is interesting that worry about hypoglycemia did not predict intentional omission of insulin injections, even though worry about hypoglycemia was high in the study population. This suggests that patients may address this worry by eating more or lowering insulin doses rather than by skipping injections altogether.