The Statistic Part of DPV

One of the main features of this program is its ability to generate statistical information about the quality of the patient's metabolism and his state of health. Furthermore a footing for comparisons  with external data is generated, as it has been demanded in the St. Vincent  declaration of 1989. This way regional differences can easily be determined. The data's logging starts with the first year values have been entered for. Each quarter's and each whole year's data will be expelled separately. To avoid mistakes due to low number of spot checks when calculating average means, the extend of data on which such a statistic is based, is given in parenthesis.

Currently the following statistics  can be produced and will be tested in chapter :

Acquisition of Achievements

computes basic information about all   patients for the institution or the physician using the database. In addition to the quantity of patients treated ambulant or stationary, the total number of ambulant medications , , of stationary receptions   and the average duration of a stay in hospital  is ascertained. Those two stationary numbers are split up into six different groups depending on the reason for being in hospital. The exact partitioning criteria are listed in chapter  on page .

Patients:

Fundamental information about the clientele's structure  is being determined. In addition to the total number of patients  who have been medicated at least once ambulant or stationary, the programs find out the percentage of male and of foreign patients . The distributions of those patients on the three types of diabetes mellitus  is also computed. The last two pieces of information given in here are the average age and the average duration of diabetes  in years.

Acute Complications:

This function calculates the quantity of hypoglycemic episodes  and ketoacidosis . This number will be transformed to a basis of 100 years. Two different definitions of heavy hypoglycemic episodes are used: 

• The help of somebody else was needed (giving sugar or an injection). This definition includes all cases with coma  or convulsion .
• Hypoglycemic episodes that cause unconsciousness  or convulsion.

Both definitions are used, but they have the following disadvantages: small children need the help of their parents  even if it is only a mild case. On the other hand, a lot of severe cases are not counted if the patient has to lose consciousness, as it is required to fulfill the second definition.

In this analysis for both definitions, two different results are computed. They differ in the interpretation of empty hypoglycemic episode fields. For the first result, it is assumed that empty fields are equal to zero, and this has just not been entered into the database. For the second result, it is assumed that empty fields have not been quantified, and so the appropriate period of time is ignored. In both cases, the total number of hypoglycemic episodes is the same, but the underlayed period of time is usually shorter in the second part. If all the fields about hypoglycemic episodes are not empty, those two results should be equal. The difference of those values indicates how earnest the user has been filling out the dialogs.

The last number computed by the function ``acute complications'' is the quantity of stationary receptions  due to an acute hyperglycemic episode or ketoacidosis after manifestation. This number will be scaled to a basis of ``100 patients per year''.

Established Complications:

As mentioned before, there is still no cure for diabetes mellitus, and   due to the usually suboptimal glucose concentration in the patient's blood, complications normally establish during the course of the disease. Some of them are made clearer in two parts:

1. The percentage of patients who suffer from retinopathy or have a albuminuria is determined. Two subdivisions into background and proliferative retinopathy and into micro- and macro-albuminuria are made.
2. The pieces of information which are mainly of interest for adult diabetics are determined here. These are the quantities of patients having problems with their feet, or suffering from postural hypotension, postural neuropathy, or erectile impotence.         

Psychosocial Environment:

As this is quite a large area, it is subdivided into the four fields: living conditions, parent's vocational education, patient's vocational education, and his origin. A full list of all entries can be received from the definitions of the appropriate dBASE tables in appendix  to starting on page .

Completeness of Control Examinations:

Since a badly adjusted metabolism of a diabetic is likely to cause irreversible damage, it is absolutely necessary to do checkups regularly. For example, patient's systolic and diastolic blood pressure, height,    weight, insulin injection sites, and his  HbA-.7ex1c have to be checked every six months, while his cholesterol level must be assessed only once a year. Albuminuria and eye checks of patients who are at least eleven years old or have had diabetes mellitus for more than five years have to be made at least once a year, too. Undoubtedly, smoking is harmful to health. Since this is especially true for diabetics, the question about the consumption of nicotine should be asked at least yearly.

The completeness of the fulfillment of those checkups which are definitely only the minimum requirements is being determined by this function.

Metabolic Controls (four parts):

As mentioned before, it is absolutely necessary to keep the metabolism of a diabetic adjusted to prevent permanent damage. Recently the molecule  HbA-.7ex1c has been used to control how this job has been done. This molecule comes into existence when glucose is bound to hemoglobin. This binding is irreversible and is dependent on the blood sugar concentration. Since  HbA-.7ex1c has a life expectancy of 120 days, it is possible to evaluate the glucose concentrations in the blood of the last eight weeks. The  HbA-.7ex1c-value is also influenced by the duration of diabetes and the patient's age. Lots more details about this chemical can be found in [Willms86]. Due to this, all data provided here will be subdivided into four groups:

$figure=patgrp.eps$

 
Figure: Groups

Four different statistics are produced using different standardization and group arrangements. This is done to avoid problems due to different ways to measure the  HbA-.7ex1c .

Therapy:

This statistic is very similar to the acquisition of achievements. The difference is that here the focus  is on the individual patient rather than on the entire set of patients. Therefore the following pieces of information are determined:

• Number of inpatient days per patient .
• Average frequency of outpatient controls.
• Number of patients who have been medicated only once.
• Share of patients who have received special instructions about handling their illness.
• Share of patients who monitor the concentration of sugar in their blood  once, up to three or more than four times a week.
• Share of patients who monitor the concentration of sugar in their urine  once or less, up to three or more than four times a week.
• Share of patients who give themselves none, one, two, three, or four insulin injections  per day.

Success of Schooling:

As long as it is not possible to cure diabetes mellitus, it is absolutely necessary to adjust the patients glucose metabolism. One way to do this is schooling the patient. This statistic evaluates the success of those educational steps. In addition to the total number of educated patients, the following values are calculated for the year before and after a schooling:

•  HbA-.7ex1c SDS median
• Body Mass Index SDS
• Systolic blood pressure SDS
• Diastolic blood pressure SDS
• Number of severe hypoglycemic episodes  per 100 patient years.

Risk Factors:

A query by means of factors which indicate a higher risk makes it possible to find endangered patients and gives the physician a chance to monitor the quality of his medications. Factors used which indicate a higher risk are:

• A body mass index above the 90th percentile.
• A height below the 10th percentile.
• A systolic blood pressure above the 90th percentile.
• A diastolic blood pressure above the 90th percentile.
• A total cholesterol concentration of 5.2 -- 6.5 mmol or even above 6.5 mmol.