Self-Pay Payer Status Predicts Long-Term Loss to Follow-Up After Bariatric Surgery

Abstract

Purpose

In spite of widespread recommendations for lifelong patient follow-up with a bariatric provider after bariatric surgery, attrition to follow-up is common. Over the past two decades, many programs have sought to expand access to care for patients lacking insurance coverage for bariatric surgery by offering “self-pay” packages; however, the impact of this financing on long-term follow-up is unclear. We sought to determine whether payer status impacts loss to follow-up within 1 year after bariatric surgery.

Materials and Methods

Records of 554 consecutive patients undergoing bariatric surgery who were eligible for 1-year post-surgical follow-up between 2014 and 2019 were retrospectively reviewed. Multiple logistic regression examined the relationship between demographics, psychological variables, payer status, and loss to follow-up.

Results

Self-pay status more than tripled the odds of loss to follow-up (OR = 3.44, p < 0.01) at 1 year following surgery. Males had more than double the odds of attrition (OR = 2.43, p < 0.01), and members of racial and ethnic minority groups (OR = 2.51, p < 0.05) were more likely to experience loss.

Conclusions

Self-pay patients, males and members of racial and ethnic minority groups, may face additional barriers to long-term access to postoperative bariatric care. Further investigation is greatly needed to develop strategies to overcome barriers to and disparities in long-term post-surgical care for more frequently lost groups.

Introduction

Lack of insurance coverage for bariatric surgery is a frequently cited reason for failure to pursue bariatric surgical care for patients who would otherwise benefit. Many institutions have attempted to navigate the lack of patient access to bariatric procedures with “self-pay” packages, which allow patients to pay out of pocket for surgery at a lower cost or utilize a healthcare savings account or installment plan. While self-pay plans are often successful in increasing patient access to local bariatric surgical care, their impact on long-term post-surgical follow-up is currently unknown.

Lifelong patient follow-up after bariatric surgery is critical to prevent postoperative weight regain, nutritional and late post-surgical complications, and weight-related comorbidity recurrence. The American Society of Metabolic and Bariatric Surgeons and the American College of Surgeons have historically advocated for lifelong follow-up with a provider trained in the care of bariatric patients as part of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP). In spite of widespread participation in this program, nationally and internationally, loss to follow-up is a problem that plagues both bariatric clinical care and research efforts designed to study the long-term safety and efficacy of bariatric procedures [1,2,3,4,5,6,7]. Multiple large series suggest progressively low rates of adherence to scheduled appointments in the postoperative period, with 30–60% of patients lost to bariatric surgical follow-up at 2 years and < 10% compliant with surgical follow-up at 10 years [3, 7].

Causes of bariatric patient loss to follow-up are poorly characterized, making interventions designed to target and alter attrition difficult to design. Practical barriers to care, especially financial ones, are among the most commonly cited reasons for loss [2,3,4]. Among those who are not compliant with recommended post-surgical follow-up, lack of insurance coverage for bariatric care has been cited as a potential reason for attrition [8]. Patients who pay out of pocket or “self-pay” for bariatric surgery may not be as motivated to pay for follow-up as they were to pay for their operation and/or may not have resources for access to long-term post-surgical follow-up.

This study seeks to examine the impact of payer status on loss to follow-up at a single university hospital which offers “self-pay” packages for patients without insurance coverage for surgery. We predicted that patients paying out of pocket for a bariatric procedure are at risk for loss to postoperative follow-up within a year of surgery.

Materials and Methods

Our institution is a contributor to the American College of Surgeons Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP). As a participating institution in this program, we track bariatric surgical patient demographics, comorbidities, operative details, and short- and long-term post-surgical outcomes as well as adherence to routine follow-up milestones and loss to follow-up among all bariatric surgical patients. Contact and scheduling attempts for patients who are overdue for scheduled follow-up are routinely included in normal clinic workflow. We attempt to contact patients who miss routine follow-up appointments with three phone calls followed by a letter from the program in order to schedule them for surgical provider and nutritional evaluation.

Using our institutional MBSAQIP database, we reviewed the records of 554 patients who received a primary Roux en Y gastric bypass (RYGB) or sleeve gastrectomy between September 2013 and October 2018 at our tertiary academic medical center. For the purposes of this study, “self-pay status” was defined as patients who paid out of pocket for a “self-pay” package prior to surgery. These packages included the entire cost of the surgical procedure and anesthesia, inpatient stay, preoperative surgeon consultation, preoperative psychological evaluation and dietary classes, and postoperative care with routine visits with a surgical provider and dietician at 3, 6, and 12 months, postoperatively, as well as an independent insurance plan which covers any complications resulting from the bariatric surgical procedure for the first year. Medicare status was defined as full or partial coverage of the procedure through Medicare; Medicaid status was defined similarly. The standard MBSAQIP definition of loss to follow-up (e.g., failure to attend the 1-year postoperative appointment within 18 months of surgery despite 4 attempts by the clinic to contact and schedule them) were used to define loss.

We also reviewed preoperative patient psychological data on levels of weight-related public distress, approach/avoidance coping style, and social support and stress, which are routinely collected through in-person assessments on all patients enrolled in our surgical program prior to bariatric surgery in order to ascertain whether these clinical metrics might correlate with follow-up attrition. Public distress was measured from a validated subscale obtained in the Impact of Weight on Quality of Life-Lite (IWQoL) measure [9]. Coping style was assessed using the coping responses inventory (CRI), a 48-item measure which asks participants to consider a significant stressor they have faced within the past year and to rate the frequency of various coping responses on a scale of 0–3 (not at all to fairly often) [10]. Subscales used in these analyses included approach coping and avoidance coping. Social support was measured by the 20-item Duke Social Support and Stress Scale (DUSOCS) (provides 2 subscales assessing social support and social stress) [11] and the 6-item Social Support Questionnaire (SSQ6, which provides information regarding both quantity and quality of social support networks [12].

Patients were categorized into two groups—those who were lost to follow-up at or before 1 year postoperatively (no bariatric surgical specialist visits between 12 and 18 months after their operation per the MBSAQIP definition of 1-year follow-up) and those who continued to follow with the bariatric surgical program at this time interval. Due to the high racial homogeneity of the sample, we were not powered to detect differences among various racial and ethnic minority groups. As such, in order to determine whether there was a gross effect of racial or ethnic minority status on loss to follow-up, we categorized patients into two groups: those who self-reported their race as White/Caucasian and those who self-identified as any other group. In order to ascertain whether being employed within our hospital system (and therefore geographic convenience to our clinic locations) confounded our sample, patient employment status was also recorded.

Data were analyzed in R. A multiple logistic regression controlling for age, gender, race, state of residence, preoperative BMI, and surgery type examined the relationship between self-pay status and loss to follow-up. An additional multiple logistic regression controlling for the same variables was used to examine whether Medicaid status predicted loss. Finally, a multiple logistic regression controlling for the same variables (excluding age, due to covariance issues) was used to test the relationship between Medicare status and loss to follow-up after bariatric surgery. In addition to these analyses, a series of univariate logistic regressions were used to examine the relationships between weight-related public distress, coping style, social support, and loss to follow-up.

Results

Five hundred fifty-four cases were included in the final dataset. Seventy-four percent of patients were female. Ninety-two percent self-reported as White, 8% as Hispanic, 2% as African American, and 4% reported as other races. Mean age was 45.17 (SD 12.4). Mean BMI was 45.20 (SD 7.6). Three hundred seventy-one patients received a Roux-en-Y gastric bypass (RYGB), while 183 received a vertical sleeve gastrectomy (SG). Seven patients were considered lost to follow-up at 6 months following surgery, and 69 were considered lost to follow-up at 12 months, for an overall institutional loss rate of 12.6% at 1 year postoperatively. Forty-two patients (7.6%) were exclusively self-pay. Seventeen percent (n = 96) of patients had part or all of their procedure costs covered by Medicare. In total, 9.7% of patients (n = 54) were covered by Medicaid. Fifteen percent of our patient sample was employed by our hospital system or the geographically adjacent university. Hospital/university employment status was found to have no significant impact on loss (Tables 1, 2, Fig. 1).

Table 1 Patient Demographics and Loss to Follow Up
Table 2 Patient Payer Status and Loss to Follow Up
Fig. 1
figure1

Multiple Logistic Regressions of Demographics and Payer Status on Loss to Follow Up: 95% CI for Odds Ratios

Psychometric Variables and Attrition

Univariate logistic regressions tested whether public distress (IWQOL-Lite), social support and stress (DUSOCS, SSQ6), and approach versus avoidant coping styles (CRI) were predictive of loss to follow-up at after bariatric surgery. None of these subscales predicted follow-up attrition at or before 1 year postoperatively.

Self-Pay and Attrition

In this multivariate analysis, gender was the strongest demographic predictor of loss to follow-up, with males more likely to be lost (OR = 2.43, p < 0.01) to follow-up at or before 1 year postoperatively. White/Caucasian patients were less likely to experience attrition at 1 year than all other racial groups (OR = 0.40, p < 0.05), while members of racial and ethnic minority groups were more likely to experience loss (OR = 2.51, p < 0.05). Increasing age also had a slightly protective effect against loss (OR = 0.98, p < 0.05). State of residence (in state versus out of state), BMI at time of surgery, and surgery type did not impact odds of loss to follow-up. After controlling for the aforementioned demographics, self-pay status was a significant predictor of loss to follow-up at or before 1 year postoperatively (OR = 3.44, p < 0.01), with self-pay patients more likely to be lost than patients with private payer coverage for surgery.

Medicare and Attrition

A multiple logistic regression controlling for gender, race, state of residence, BMI, and procedure type examined whether Medicare status had a significant impact on loss to follow-up. Age was excluded as a control variable due to high covariance with Medicare status. Demographic predictors exhibited a similar predictive pattern in this model as the self-pay model, with male patients at higher risk for loss (OR = 2.21, p < .01) and White/Caucasian patients at lower risk (OR = 0.40, p < 0.05). After controlling for the aforementioned predictors, Medicare patients demonstrated less than half the odds of attrition compared to their non-Medicare counterparts (OR = 0.37, p < 0.05).

Medicaid and Attrition

An additional logistic model tested the impact of Medicaid coverage on postoperative loss to follow-up. Though Medicaid status seemed to be a trending predictor of loss in a univariate logistic regression (OR = 1.91, p = 0.08), this trend was no longer significant after controlling for age, gender, race, state of residence, BMI, and surgery type (OR = 1.68, p = 0.18).

Conclusion

Although the American Society of Metabolic and Bariatric Surgery encourages all bariatric surgical practices to maintain lifetime follow-up with their patients to assess for long-term surgical and nutritional complications and reinforce lifestyle modifications conducive to ongoing weight loss, bariatric surgery is plagued by a high rate of attrition to long-term follow-up. Other groups have shown that approximately 40% of all bariatric surgical patients are lost to follow-up after 14 months, with attrition rates as high as 90% after 10 years [1, 3, 6, 7]. Those who are lost to follow-up tend to experience less durable weight loss after surgery [1, 5, 13] and are at risk for unrecognized vitamin and mineral deficiencies [10].

Surprisingly, despite ubiquitous attrition following bariatric surgery, very few studies attempt to ascertain reasons for loss. A systematic literature review conducted in 2012 found only 8 studies on this topic, with inconsistencies in methods and results making consensus interpretation difficult [3]. Of these studies, most were underpowered to detect small or even medium effect sizes, and there was little overlap in predictors examined. This pattern continues in more recent literature, for example, with small studies predicting attrition with particular variables assessed in isolation such as avoidant relationship style and distance from home to hospital identified as predictors of attrition [2,3,4].

Though studies of post bariatric surgical attrition have been retrospective and quantitative in nature, one qualitative study conducted in Italy yielded more granular information on attrition to a medical weight loss program [2]. Grossi and colleagues conducted semi-structured phone interviews with 904 Italian patients who dropped out of non-surgical weight loss treatment in Italy. They found that the most common reported reasons for attrition were practical concerns—especially difficulties with family, work, and distance to the treatment center [2]. While these factors may be hypothesized to have an impact on post-surgical follow-up as well, it is important to note that the aforementioned qualitative study was not impacted by lack of insurance for follow-up, as medical insurance is a universal benefit under the Italian National Health Service [2].

Bariatric surgical care occupies a unique position in the American insurance world. In spite of dramatic improvements in weight-related comorbidities following bariatric surgery, many insurance companies have specific benefit exclusions for some or all aspects of bariatric surgical procedures. Moreover, though bariatric surgery is considered to be a cost-effective procedure (as measured by improvements in lifetime benefits in patient health), the evidence on whether surgery is cost saving for payers over a short-term period is more mixed, leading to an insurance culture that is not conducive to access to obesity care [14,15,16,17,18]. Thus, due to these economic factors, even a patient who has health insurance may be under-insured or forced to pay entirely out of pocket for a bariatric procedure.

Various studies have examined the impact of insurance status on patient attrition to behavioral intervention programs. Across the board, lack of health insurance and self-pay status predict increased loss to follow-up in health behavior intervention and medical weight loss settings [19, 20]. Uninsured patients have been found to have worse health outcomes with diabetes management and medical weight loss interventions, though the research is more mixed regarding self-pay patients, possibly due to the confounding influence of self-pay patients’ tendency to have higher socioeconomic status [21, 22].

Though previous work has queried whether bariatric patients with government-provided insurance have worse outcomes after surgery, there is limited data supporting this for bariatric surgical patients. Medicaid patients seem to have higher BMIs at time of initial presentation but have similar overall response to surgery as their privately insured counterparts [23, 24]. Our study provided limited support to the perception that Medicaid patients are at higher risk for loss to follow-up after surgery; however, the fact that this trending relationship disappeared after controlling for demographic variables suggests that this is an unreliable predictor of attrition. While there are significant flaws in using Medicaid payer status as a surrogate for socioeconomic status, we did not have more direct measures of socioeconomic status, such as household income, patient occupation, or personal and familial educational attainment to further inform our study. Future research investigating these effects is needed in order to allow physicians to more accurately characterize and compensate for barriers to follow up for Medicaid patients.

In a systematic review of predictors of attrition to behavioral weight loss interventions, Moroshko and colleagues reviewed 61 studies assessing factors associated with attrition to weight loss programs [3]. They found 33 studies which evaluated the effects of patient age on attrition—17 found no relationship, 2 studies found that older patients were more likely to drop out of treatment, and the remaining 13 found that younger patient age was associated with higher rates of attrition [3]. Additionally, 12/16 studies found no relationship between patient gender and attrition and only one that reported male gender as a corollary with attrition [3]. Our study in our surgical population found that both increasing age and Medicare status are protective against postoperative loss to follow-up. However, one could easily argue that this is a singular finding, as age and Medicare status significantly covary. Moreover, underlying confounding variables—retirement and the greater flexibility in scheduling that this provides combined with increased age-related comorbidities—may in fact be driving this relationship. Though the current study did not measure patients’ employment or retirement status, future research into postoperative loss to follow-up would benefit from a more granular approach to the measurement of patients’ ability to follow-up.

It is important to note that there are certain factors that make our institution unique, limiting the generalizability of this study. Our surgical program is located in the western USA at an institution with a wide geographic catchment area spanning several states. Patient experience within our large interstate geographic catchment area is not necessarily translatable to the experience of American institutions that compete for patients within a very small geographic area, particularly in terms of the potential effects of interstate barriers on loss to follow-up.

While we found disparities in adherence to long-term follow-up for patients of non-White race, our study is also limited by its racial homogeneity. As we were not able to test whether patients of various racial and ethnic minority groups have varying rates of loss to follow-up, our study lacks granularity in its description of this effect for individual racial and ethnic groups. Past research on behavioral and medical weight loss programs have shown mixed results on whether patients of different racial and/or ethnic minority groups are at higher risk of program attrition, with multiple studies reporting confounding variables such as treatment time, percent excess weight loss, socioeconomic factors, and education level. More work is clearly needed in this area to determine the factors which may lead to disparities in long-term post-surgical follow-up and potential impact on care for patients of racial and ethnic minorities.

Finally, our dataset has a very restricted time range. The first surgery conducted at our institution was performed in 2011. As the program has grown over time with the addition of more surgeons and staff, most of the surgeries have occurred fairly recently. As examining longer-term loss to follow-up would reduce power, we restricted our analyses to early attrition within the first 12 months of surgery. While we anticipate that effects seen at 12 months would persist over longer time periods, further research is needed to determine whether our findings persist or amplify over time.

Patient non-compliance with recommended long-term follow-up visits is common after the roughly 230,000 bariatric procedures performed in the USA annually and associated with postoperative complications, malnutrition, and weight regain. In addition to focusing on weight maintenance and avoiding weight regain, long-term postoperative bariatric surgical visits are designed to identify risk factors for and signs of early or late operative complications and identify and treat malnutrition. Unfortunately, it is not uncommon for patients with a history of follow-up attrition to present to the emergency department with a preventable bariatric surgical complication, such as a perforated ulcer, ischemic bowel from an internal hernia, or symptomatic nutritional deficiency such as peripheral neuropathy or Wernicke’s encephalopathy. While these complications are a significant source of morbidity, for patients without insurance for bariatric care, there are also potential significant financial consequences of these complications. In order to decrease the long-term morbidity of bariatric surgery and further improve its overall health benefits, there is a critical need to facilitate long-term follow-up for patients, regardless of insurance barriers, and to provide anticipatory guidance designed to prevent patient presentation for urgent or emergent care for late postoperative complications. In the absence of such mechanisms, the potential to further improve the long-term safety and benefits of bariatric surgery will likely remain limited.

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Acknowledgments

The authors wish to acknowledge our patients and their families, from whom we are continually learning, and all those who advocate for and provide quality care to patients with obesity.

Funding

Research reported in this publication was supported by the National Center for Advancing Translational Sciences of the National Institutes of Health under Award Number UL1TR002538.

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Correspondence to Anna R. Ibele.

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Drs. Ibele, McGarrity, Volckmann, and Morrow and Ms. Kohler, Martinez, and Turner have no active or potential personal business or financial conflicts of interest related to the enclosed research. Ms. Martinez previously served part time as site coordinator for a clinical trial conducted by the Rhythm Pharmaceuticals which was unrelated to the content of this work.

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Institutional Review Board approval was obtained prior to the conduct of this research. As this was a retrospective study, informed consent for research participation was deemed exempt by our Institutional Review Board. This work has not been previously published, and consent to submit has been received from all co-authors and responsible authorities at the institution where this work has been carried out. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

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Martinez, P.L., McGarrity, L.A., Turner, N.A. et al. Self-Pay Payer Status Predicts Long-Term Loss to Follow-Up After Bariatric Surgery. OBES SURG (2021). https://doi.org/10.1007/s11695-020-05161-4

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Keywords

  • Bariatric surgery
  • Insurance
  • Self-pay
  • Payer
  • Outcomes
  • Loss to follow-up
  • Attrition
  • Disparities
  • Gender
  • Ethnicity