Association between evacuation and becoming overweight after the Great East Japan Earthquake: a 7-year follow-up of the Fukushima Health Management Survey.

OBJECTIVES: Disaster evacuation increases the risk of becoming overweight or obese owing to lifestyle changes and psychosocial factors. This study evaluated the effect of evacuation on becoming overweight during a 7-year follow-up among residents of Fukushima Prefecture during the Great East Japan Earthquake. STUDY DESIGN: This was a prospective cohort study. METHODS: We analysed data collected from 18,977 non-overweight Japanese participants who completed the 'Comprehensive Health Checkup Program' and 'Mental Health and Lifestyle Survey', as part of the Fukushima Health Management Survey, between July 2011 and November 2012. An evacuation was defined as the moving out of residents of municipalities designated as an evacuation zone by the government or having a self-reported experience of moving into shelters or temporary housing. Follow-up examinations were conducted in March 2018 to identify patients who became overweight. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated using a Cox proportional hazards regression model. RESULTS: Among 15,875 participants (6091 men and 9784 women; mean age 63.0 ± 11.1 years) who received follow-up examination (mean follow-up, 4.29 years), 2042 (856 men and 1186 women) became overweight. Age-, baseline body mass index-, lifestyle-, and psychosocial status-adjusted HRs (95% CIs) for becoming overweight after evacuation were 1.44 (1.24-1.66) for men and 1.66 (1.47-1.89) for women. CONCLUSION: Evacuation was associated with the risk of becoming overweight 7 years after the disaster. Thus, maintaining physical activity, healthy diet, and sleep quality and removing barriers to healthy behaviour caused by disasters, including anxiety concerning radiation, may prevent this health risk among evacuees.

Subjective Well-Being Is Associated with Food Behavior and Demographic Factors in Chronically Ill Older Japanese People Living Alone.

OBJECTIVES: This study aimed to examine the relationships among subjective well-being, food and health behaviors, socioeconomic factors, and geography in chronically ill older Japanese adults living alone. DESIGN: The design was a cross-sectional, multilevel survey. A questionnaire was distributed by post and self-completed by participants. SETTING: The sample was drawn from seven towns and cities across Japan. PARTICIPANTS: A geographic information system was used to select a representative sample of older people living alone based on their proximity to a supermarket. Study recruitment was conducted with municipal assistance. MEASUREMENTS: To assess subjective well-being and food and health behaviors of respondents with disease, a logistic regression analysis was performed using stepwise variable analyses, adjusted for respondent age, socioeconomic status, and proximity to a supermarket. The dependent variable was good or poor subjective well-being. RESULTS: In total, 2,165 older people (744 men, 1,421 women) completed the questionnaire (63.5% response rate). Data from 737 men and 1,414 women were used in this study. Among people with a chronic disease, individuals with good subjective well-being had significantly higher rates than those with poor subjective well-being for satisfaction with meal quality and chewing ability, food diversity, food intake frequency, perception of shopping ease, having someone to help with food shopping, eating home-produced vegetables, preparing breakfast themselves, eating with other people, and high alcohol consumption. A stepwise logistic analysis showed that the factors strongly related to poor subjective well-being were shopping difficulty (men: odds ratio [OR] = 3.19, 95% confidence interval [CI], 1.94-5.23; P < 0.0001; women: OR = 2.20, 95% CI, 1.54-3.14; P < 0.0001), not having someone to help with food shopping (women: OR = 1.41, 95% CI, 1.01-1.97; P = 0.043), not preparing breakfast (women: OR = 2.36, 95% CI, 1.40-3.98; P = 0.001), and eating together less often (women: OR = 1.99, 95% CI, 1.32-3.00; P = 0.002). CONCLUSION: Subjective well-being of people with chronic diseases is associated with food intake and food behavior. The factors that affect poor subjective well-being in chronically ill older Japanese people living alone include food accessibility and social communication.

"Eating Together" Is Associated with Food Behaviors and Demographic Factors of Older Japanese People Who Live Alone.

OBJECTIVE: This study aimed to examine the relationships between eating together and subjective health, frailty, food behaviors, food accessibility, food production, meal preparation, alcohol intake, socioeconomic factors and geography among older Japanese people who live alone. DESIGN: A cross-sectional, multilevel survey was designed. The questionnaire was distributed by post and self-completed by participants. SETTING: The sample was drawn from seven towns and cities across Japan. PARTICIPANTS: A geographic information system was used to select a representative sample of older people who lived alone based on their proximity to a supermarket. Recruitment for the study was conducted with municipal assistance. MEASUREMENTS: A logistic regression analysis was performed that adjusted for the respondent's age, socioeconomic status and proximity to a supermarket using stepwise variable analyses. The dependent variable was whether the respondent ate together more or less than once a month. RESULTS: In total, 2,196 older people (752 men and 1,444 women) completed the questionnaire (63.5% response rate). It was found that 47.1% of men and 23.9% of women ate together less than once a month. Those who ate together less than once a month had a significantly lower rate of subjective health, food diversity and food intake frequency than those who ate together more often. A stepwise logistic analysis showed that the factors most strongly related to eating together less than once a month were not having any food shopping assistance (men: OR = 3.06, women: OR = 2.71), not receiving any food from neighbors or relatives (men: OR = 1.74, women: OR = 1.82), daily alcohol intake (women: OR = 1.83), frailty (men: OR = 0.48) and income (men: OR = 2.16, women: OR = 1.32). CONCLUSION: Eating together is associated with subjective health and food intake. Factors that affect how often older Japanese people who live alone eat together include food accessibility, daily alcohol intake, frailty and a low income.

Unexpected monophyletic origin of Ephoron shigae unisexual reproduction strains and their rapid expansion across Japan.

The burrowing polymitarcyid mayfly Ephoron shigae is distributed across Japan, Korea, northeast China and far east Russia. Some populations are bisexual, and others are unisexual, i.e. geographically parthenogenetic throughout Japan. In general, parthenogenetic organisms are often found in harsh environments, such as at high latitudes and altitudes, in xeric as opposed to mesic conditions, in isolated habitats such as islands and island-like areas, and at the peripheral regions of the taxon's range. In E. shigae, however, the distributions of bisexual and unisexual populations overlap broadly in their respective geographical ranges. In the analysis of mitochondrial 16S rRNA and COI, we revealed that unisexual populations were of monophyletic origin and recently differentiated somewhere in western Japan. In the nuclear DNA EFI-α analysis, parthenogenetic strains had two genotypes, i.e. the heterozygous genotype of E1/E3 and the homozygous genotype of E1/E1 or E3/E3, while specimens of bisexual lineage had 20 genotypes. These results are consistent with an automixis mode of reproduction for the parthenogenetic strains, and also support the monophyletic origin of the parthenogenetic strains. Furthermore, there would be no gene flow between the specimens of the bisexual lineage and those of the parthenogenetic strain.

Association of the -31C/T functional polymorphism in the interleukin-1beta gene with the intractability of Graves' disease and the proportion of T helper type 17 cells.

Interleukin (IL)-1beta is a proinflammatory cytokine and has been implicated in the pathogenesis of several autoimmune diseases. To evaluate the hypothesis that the functional -31C/T polymorphism (rs1143627) in the gene encoding IL-1beta is associated with the intractability and the severity of autoimmune thyroid diseases, we genotyped this polymorphism in 64 patients with intractable Graves' disease (GD), 28 GD patients in remission, 49 patients with Hashimoto's disease (HD) who developed hypothyroidism (severe HD), 28 untreated euthyroid HD patients (mild HD) and 59 healthy volunteers. The -31T allele, which is related to the high producibility of IL-1beta, was significantly more frequent in patients with intractable GD than in those with GD in remission (P = 0.0017; odds ratio 2.8; 95% confidence interval 1.5-5.3), although there was no difference in this frequency between two groups of HD patients. We showed additionally that the proportion of IL-17-producing T helper type 17 (Th17) cells, whose differentiation and proliferation are promoted by IL-1beta, was higher in autoimmune thyroid disease patients with the T allele than in those with CC genotypes. In conclusion, our data indicated that the T allele of -31C/T polymorphism in the IL1B gene was involved in the intractability of GD, and this involvement may arise through the differentiation and proliferation of Th17 cells.

Demographics, health-related behaviors, eating habits and knowledge associated with vegetable intake in Japanese adults.

OBJECTIVES: To analyze demographic, health-related behaviors, eating habit and knowledge associated with vegetable intake. METHODS: Secondary analyses using the dataset from the National Health and Nutrition Survey 2003. Food intake data measured by the food-weighing method in one-day and a questionnaire assessed the dietary intake and health-related behaviors, eating habit and knowledge. This study was made in Japan. The data of 1742 men and 2519 nonpregnant/nonlactating women, aged 20-69 years, energy intake between percentiles 1 and 99 were included. Vegetable intake was analyzed according to the Japanese vegetable recommendation (>or=350 g/day) after age adjustment. RESULTS: Average of VI was 307 g/day in men and 297 g/day in women. Only 35% of men and 31% of women met the recommended amount of vegetable intake. Japanese from city areas, aged 60-69 years, had the highest vegetable intake and subjects from metropolitan areas had the lowest vegetable intake. Depending on the age groups, risks for low vegetable intake in Japanese were found in subjects with skipping meals, alcohol intake and history of smoking. CONCLUSIONS: To increase vegetable intake, it is necessary to provide more nutritional education and lifestyle-related diseases education.

Role of gap junctions in spontaneous activity of the rat bladder.

Increased gap junction expression in lamina propria myofibroblasts and urothelial cells may be involved in detrusor overactivity, leading to incontinence. Immunohistochemistry was used to compare connexin (Cx) 26, 43, and 45 expression in the bladders of neonatal, adult, and spinal cord-transected rats, while optical imaging was used to map the spread of spontaneous activity and the effects of gap junction blockade. Female adult Sprague-Dawley rats were deeply anesthetized, a laminectomy was performed, and the spinal cord was transected (T8/T9). After 14 days, their bladders and those of age-matched adults (4 mo old) and neonates (7-21 day old) were excised and studied immunohistochemically using frozen sections or optically using whole bladders stained with voltage- and Ca(2+)-sensitive dyes. The expression of Cx26 was localized to the urothelium, Cx43 to the lamina propria myofibroblasts, and Cx45 to the detrusor smooth muscle. While the expression of Cx45 was comparable in all bladders, the expression of Cx43 and Cx26 was increased in neonate and transected animals. In the bladders of adults, spontaneous activity was initiated at multiple sites, resulting in a lack of coordination. Alternatively, in neonate and transected animals spontaneous activity was initiated at a focal site near the dome and spread in a coordinated fashion throughout the bladder. Gap junction blockade (18beta-glycyrrhetinic acid, 1 microM) abolished this coordinated activity but had no effect on the uncoordinated activity in adult bladders. These data suggest that coordinated spontaneous activity requires gap junction upregulation in urothelial cells and lamina propria myofibroblasts.

Perceived body size and desire for thinness of young Japanese women: a population-based survey.

The present study describes findings in relation to perceived body size and 'desire for thinness' by age and residential areas ('metropolitan areas', 'large cities', 'small cities' and 'towns') among young Japanese women. Data on 1731 non-pregnant, non-lactating women aged 15-39 years from the 1998 National Nutrition Survey of Japan were used. Current body size was evaluated by BMI percentiles (lean, <5th; underweight, 5th or = BMI <25th; normal, 25th< or = BMI< 75th; overweight, 75th < or =BMI <95th; obese, > or =95th), calculated for 5-year age groups. Perceived body size was obtained by self-report. We defined 'overestimation' as non-overweight, non-obese women who perceived themselves as being 'overweight' or 'obese'. Desired body size was evaluated by applying the desired BMI to these cut-off points. Of all the women, 48.4% perceived themselves as being 'overweight' or 'obese', and 43.7% desired a 'lean' or 'underweight' body size. Adjusted for the current BMI, the OR for 'overestimation' calculated by a logistic regression model was significantly elevated in the 15-19-year age group (OR 2.79; 95% CI 1.76, 4.43), compared with the 25-29-year age group. The OR for 'desire for thinness' was significantly high in the 35-39-year age group (OR 2.74; 95% CI 1.93, 3.89) and the 15-19-year age group (OR 2.26; 95% CI 1.57, 3.24). Women living in metropolitan areas had higher OR for 'desire for thinness' (but not for 'overestimation') than did women in towns (OR 1.47; 95% CI 1.05, 2.07). The findings suggest the nature of excessive weight concerns of young women in Japan; thus efforts to control such health-risk behaviours at a national level are urgent.

Comparison of the collecting efficiency of microbiological air samplers.

It is important to evaluate the prevention of nosocomial infections caused by airborne micro-organisms in healthcare facilities. For that purpose, the use of an air sampler is required. A comparison of the collecting efficiency of air samplers has not been studied so far using a single culture medium. Use of the same culture medium is necessary because of the variation of the cultivation efficiency with different culture media. In this study a statistically significant difference in collecting efficiency among air samplers was observed in case of SCDA (soybean casein digest agar) culture medium, but not SCDALP (soybean casein digest agar lecithin polysorbate) culture medium. In addition, a statistically significant difference of the cultivation efficiency was observed between SCDA and SCDALP culture media (P<0.05). These results suggest that any air sampler can be used with SCDALP culture medium.

Short-term plasticity of descending synaptic input to phrenic motoneurons in rats.

Respiratory afferent stimulation can elicit increases in respiratory motor output that outlast the period of stimulation by seconds to minutes [short-term potentiation (STP)]. This study examined the potential contribution of spinal mechanisms to STP in anesthetized, vagotomized, paralyzed rats. After C(1) spinal cord transection, stimulus trains (100 Hz, 5-60 s) of the C(1)-C(2) lateral funiculus elicited STP of phrenic nerve activity that peaked several seconds poststimulation. Intracellular recording revealed that individual phrenic motoneurons exhibited one of three different responses to stimulation: 1) depolarization that peaked several seconds poststimulation, 2) depolarization during stimulation and then exponential repolarization after stimulation, and 3) bistable behavior in which motoneurons depolarized to a new, relatively stable level that was maintained after stimulus termination. During the STP, excitatory postsynaptic potentials elicited by single-stimulus pulses were larger and longer. In conclusion, repetitive activation of the descending inputs to phrenic motoneurons causes a short-lasting depolarization of phrenic motoneurons, and augmentation of excitatory postsynaptic potentials, consistent with a contribution to STP.

Effect of cataract surgery on intraocular pressure control in glaucoma patients.

PURPOSE: To examine the effect of cataract surgery on intraocular pressure (IOP) control in eyes with angle-closure glaucoma (ACG) and open-angle glaucoma (OAG). SETTING: Hayashi Eye Hospital, Fukuoka, Japan. METHODS: This study included 74 eyes with ACG and 68 eyes with OAG having cataract surgery. The IOP was measured and the number of glaucoma medications recorded preoperatively, 1 month postoperatively, and then every 3 months. The IOP control in the 2 groups was compared using survival analysis, with failure criteria being an IOP greater than 21 mm Hg, addition of medications, or the need for additional glaucoma surgery. RESULTS: The mean IOP and number of medications decreased significantly after surgery in both groups (P <.0001). However, the mean decrease in IOP and percentage of IOP reduction in the ACG group were greater than in the OAG group, and fewer medications were required in the ACG group. The cumulative survival probability of IOP control at 24 months was 91.9% in the ACG group and 72.1% in the OAG group. The survival curve in the ACG group was significantly better than in the OAG group (P =.0012). The IOP was controlled without medication in 30 eyes (40.5%) in the ACG group and 13 (19.1%) in the OAG group; the difference between groups was significant (P =.0055). CONCLUSIONS: Cataract surgery substantially reduced IOP and the number of medications required for IOP control in glaucomatous eyes. Specifically, cataract extraction normalized the IOP in most eyes with ACG.

Correlation between pupillary size and intraocular lens decentration and visual acuity of a zonal-progressive multifocal lens and a monofocal lens.

OBJECTIVE: To see whether there is a correlation between pupillary area or intraocular lens (IOL) decentration and tilt and the visual acuity (VA) at all distances for eyes with a zonal-progressive multifocal IOL or a monofocal IOL. DESIGN: Comparative, nonrandomized, interventional study. PARTICIPANTS: Fifty-five eyes of 55 patients undergoing five-zone refractive multifocal IOL implantation and 55 eyes of 55 age-matched patients undergoing monofocal IOL implantation. INTERVENTION: All eyes underwent phacoemulsification and IOL implantation. MAIN OUTCOME MEASURES: The VAs from far to near distances were examined using an all-distance vision tester at 1 month after surgery. The pupillary area was also measured using an infrared pupillometer, and the degrees of IOL decentration and tilt were measured using a Scheimpflug videophotography system. Univariate associations between VA and the pupillary area and IOL decentration or tilt were evaluated statistically. RESULTS: The mean intermediate VAs and contrast sensitivities at all spatial frequencies in the multifocal IOL group were worse than those in the monofocal IOL group, whereas near VA was better in the multifocal group. In the multifocal group, smaller pupillary area was associated significantly with worse near logarithm of the minimum angle of resolution (LogMAR) VA (r = 0.636), but not with far or intermediate VAs. When pupil diameter was 4.5 mm or greater, near mean VA reached 20/63. A greater degree of IOL decentration was associated significantly with worse far and intermediate LogMAR VAs (r = 0.460 at 5.0 m and 0.527 at 1.0 m) but not with near VA. When decentration was 0.9 mm or greater, distance mean VA did not reach 20/32. However, the correlation between tilt and VA was not statistically significant. In the monofocal group, no significant correlation was found between pupillary area, IOL decentration, or tilt and the VA. CONCLUSIONS: Smaller pupil size is correlated significantly with worse near VA, whereas greater decentration is correlated with worse distance and intermediate VA in eyes with refractive multifocal IOLs. Specifically, a pupil diameter of less than 4.5 mm cannot provide useful near VA, and decentration of 0.9 mm is the maximum allowable limit for adequate distance VA. However, pupil size and IOL decentration do not influence VA in eyes with monofocal IOLs.

[Chronobiological case study on cardiac responses during aerobic exercise].

50% HR reserve aerobic exercise on a bicycle ergometer was carried out for 20 min each time by a slightly obese male aged 70 years old from October, 1998 to August, 2000 at 8:00 AM (Mor. Ex.) or 17:00 PM (Even. Ex.). The same exercise was carried out at random times during the day from January to March, 2000. The following five indicators were measured: the heart rate in the first minute of exercise, the time until the attainment of the target heart rate, the loaded power at the time of attaining the target heart rate, the energy consumption during exercise, and RPE on the Borg Scale. The effects of Jet lag were also observed three times during that period. The following results were obtained. I. The changes in indicators with the progress of exercise; 1. The heart rate after the first minute of exercise was increased in the Mor. Ex. 2. The time until attainment of the target heart rate was shortened in the Mor. Ex., but it was unchanged in the Even. Ex. 3. The loaded power at the time when the target heart rate was attained decreased in the Mor. Ex., but it was unchanged in the Even. Ex. 4. Energy consumption decreased in the Mor. Ex., and increased in the Even. Ex. 5. The RPE decreased in the Mor. Ex., but increased in the Even. Ex. The abovementioned changes were not due to seasonal variations. II. The effects of exercise became stable at and after six months in the Mor. Ex., and nine months in the Even. Ex. III. The differences between Mor. Ex., and Even. Ex. in all the indicators were significant. IV. The coefficient of correlation between the energy consumption and heart rate at the end of the first minute of exercise was significantly inverse. V. Energy consumption during exercise increased from 8:00 AM and left the range of morning response at 9:30 AM and entered the range of evening response on and after 11:00 AM. It decreased for a short time after lunch. VI. The effect of Jet lag was observed as a lowering of energy consumption during exercise in the Even. Ex., and two or four days were required for recovery.

Anterior capsule contraction and intraocular lens decentration and tilt after hydrogel lens implantation.

AIM: To prospectively investigate changes in the area of the anterior capsule opening, and intraocular lens (IOL) decentration and tilt after implantation of a hydrogel IOL. METHODS: 100 patients underwent implantation of a hydrogel IOL in one eye and an acrylic IOL implantation in the opposite eye. The area of the anterior capsule opening, and the degree of IOL decentration and tilt were measured using the Scheimpflug videophotography system at 3 days, and at 1, 3, and 6 months postoperatively. RESULTS: The mean anterior capsule opening area decreased significantly in both groups. At 6 months postoperatively, the area in the hydrogel group was significantly smaller than that in the acrylic group. The mean percentage of the area reduction in the hydrogel group was also significantly greater than that in the acrylic group, being 16.9% in the hydrogel group and 8.8% in the acrylic group. In contrast, IOL decentration and tilt did not progress in either group. No significant differences were found in the degree of IOL decentration and tilt throughout the follow up period. CONCLUSIONS: Contraction of the anterior capsule opening was more extensive with the hydrogel IOL than with the acrylic IOL, but the degree of IOL decentration and tilt were similar for the two types of lenses studied.

Purification and characterization of Delta(1)-pyrroline-5-carboxylate reductase isoenzymes, indicating differential distribution in spinach (Spinacia oleracea L.) leaves.

Delta(1)-Pyrroline-5-carboxylate reductase (P5CR) (EC 1.5.1.2. L-proline: NAD(P)-5-oxidoreductase), the second enzyme in the proline biosynthetic pathway, was purified from spinach (Spinacia oleracea L.) leaves. Following ammonium sulfate fractionation, purification was performed by several chromatographic methods: Blue Cellulofine, DEAE-TOYOPEARL, Sephacryl S-300 HR, and POROS QE/M. Two isoenzymes resolved by anion exchange chromatography were designated P5CR-1 and P5CR-2. Only P5CR-2 was purified from the intact chloroplasts, indicating differential distribution of the isoenzymes. P5CR isoenzymes, P5CR-1 and P5CR-2, are a homopolymer with an apparent molecular mass of 310 kDa, consisting of 10 to 12 subunits of about 28.5 kDa. P5CR-1 and P5CR-2 showed K(m) values of 9 and 19 microM for NADPH and values of 0.122 and 0.162 mM for Delta(1)-pyrroline-5-carboxylate (P5C), respectively. We decided partial amino acid sequences of P5CR-1 which showed the 70 to 80% homology to the deduced amino acid sequences of several plant P5CR cDNAs. Both isoenzymes had much lower affinity for NADH than for NADPH and were inhibited by free ATP and Mg(2+) ion. The inhibition was partially mitigated when ATP and Mg(2+) were added simultaneously to the reaction mixture. Cations at high concentration were inhibitory to P5CR activity. Interestingly, P5CR-2 was more stable to heat treatment at 40 degrees C than P5CR-1.

Influence of cataract surgery on automated perimetry in patients with glaucoma.

PURPOSE: To investigate the influence of cataract surgery on automated perimetry in patients with glaucoma. DESIGN: Interventional case series. METHODS: A total of 105 eyes of 105 consecutive patients with glaucoma who were scheduled for cataract surgery underwent Humphrey static threshold testing (30-2 program) before and at 1 month after surgery. These eyes were divided into two groups based on the presence of absolute or near absolute (dense) scotomata before surgery (minimum threshold value 5 decibels or less). Changes in numbers of the dense scotomata, mean deviation, pattern standard deviation, and corrected pattern standard deviation were analyzed. RESULTS: No significant changes were found in the numbers of dense scotomata and central dense scotomata within five-degree visual fields between before and after surgery. In the group with dense scotomata, the mean pattern standard deviation and corrected pattern standard deviation worsened significantly after surgery, whereas the mean deviation improved significantly. However, in the group without dense scotomata, the pattern standard deviation and corrected pattern standard deviation showed a slight improvement, whereas the mean deviation improved significantly. When the central scotoma was present in two or fewer meridians before surgery, the mean visual acuity after surgery reached 20/25 and was better than that in patients with three or four central scotomata (P =.0014). CONCLUSIONS: Cataract does not produce a dense scotoma on automated perimetry. However, because it does produce relative scotomata, actual glaucomatous visual field defects may be hidden to some extent. When a central dense scotoma is present before surgery in two or fewer meridians, the patient may well achieve substantial improvement in postoperative visual acuity.

Changes in posterior capsule opacification after poly(methyl methacrylate), silicone, and acrylic intraocular lens implantation.

PURPOSE: To prospectively evaluate the progression of posterior capsule opacification (PCO) after poly(methyl methacrylate) (PMMA), silicone, and acrylic intraocular lens (IOL) implantation. SETTING: Hayashi Eye Hospital, Fukuoka, Japan. METHODS: Three hundred eyes of 300 patients scheduled to have IOL implantation were initially randomized into 3 groups based on IOL type: PMMA, silicone, or acrylic. Of the 300 eyes, 269 completed the follow-up. The PCO density in these eyes was measured 1 week and 3, 6, 12, 18, and 24 months postoperatively using special computer software developed for the Scheimpflug videophotography system. Visual acuity and the incidence of neodymium:YAG (Nd:YAG) laser capsulotomy were also examined. RESULTS: Three months postoperatively and later, the mean PCO value in the PMMA group increased significantly (P <.0001); the increase in the silicone and acrylic groups was not significant. The PCO value in the PMMA group was significantly greater than in the silicone or acrylic group (P <.0001). The PCO value in the acrylic group was slightly less than in the silicone group at 18 and 24 months, but the difference was marginal. The survival rate not requiring Nd:YAG capsulotomy was least in the PMMA group, followed by the silicone and acrylic groups in that order (P <.0001). The mean logMAR visual acuity in the PMMA group increased postoperatively and was worse than in the silicone or acrylic group. CONCLUSIONS: The degree of PCO after PMMA IOL implantation progressed significantly with time, while the progression after silicone and acrylic IOL implantation was slight. Therefore, PCO in eyes with a PMMA IOL was significantly more extensive than in those with a silicone or acrylic IOL and resulted in marked impairment of visual acuity.